UC-NRLF 


R     1     P,^7     ^7U 


ASTBOIOMICAL  AID  HISTOEICAI 


CHROlOIOai 


W.  LEIGHTON  JOEBAN 


mmmmmm'f-^i 


BrrsE 


ASTEONOMIOAL  AND   mSTOHlCAL 
CHRONOLOGY 

IN   THE   BATTLE   OF   THE   CENTURIES 


BY 

WILLIAM  LEIGHTON   JOEDAN 

FELLOW  OP  THE  ROYAL  INSTITUTION  OP  GREAT  BRITAIN  ;  FELLOW  OF  THE 

ROYAL    STATISTICAL   SOCIETY 

ASSOCIATE    OP    THE    INSTITUTION    OP    CIVIL    ENGINEERS 

FELLOW  OP  THE  ROYAL  METEOROLOGICAL  SOCIETY 

FELLOW  OP  THE  ROYAL  GEOGRAPHICAL  SOCIETY  ;  FELLOW  OP  THK  SOCIETY  OP  ARTS 

PAST    PRESIDENT    OP    THE    ENGLISH    LITERARY    SOCIETY 

OP  BUENOS  AYRES 


ff    ^        or  THE  ^'^P 

''    UNIVER3/TY 


LONGMANS,     GKEEN,    AND    CO. 

39    PATERNOSTER    ROW,    LONDON 

NEW   YORK    AND    BOMBAY 

1904 

All    rights    reserved 


c.^n\ 


f^  ^J>^ 


^iisE 


'4L 


I    DEDICATE   THIS    LITTLE   BOOK 

TO   ALL   LIBRAEIANS 

IN    THE   CITIES   OP   FLORENCE   AND    PISA 

OP   GLORIOUS   RENOWN 

IN    THE    HOPE    THAT    THROUGH    SO    DOING    I    MAY    RECEIVE 

PROM    SOME   AMONG    THEM 

FURTHER   EVIDENCE   FOR   THE   ELUCIDATION 

OP   THE   SUBJECT 


PEEFAOE 


The  following  Argument  (excepting  the  references  to 
the  State  Library  of  Venice  and  to  the  1875  edition 
of  Bond's  '  Chronology  ' )  was  written  in  the  year  1900, 
when  discussion  was  rife  as  to  whether  that  year 
properly  belongs  to  the  nineteenth  or  to  the  twentieth 
century ;  and  I  have  retained  it  as  a  basis  for  argument, 
as  it  sometimes  simplifies  references  and  discussion. 

I  have  used  the  term  historical  rather  than  the 
usual  term  vulgar  chronology  in  the  title  because 
the  origin  of  the  latter  term  makes  it  properly  include 
astronomical  chronology,  it  having  been  intended  to 
signify  that  it  does  not  give  the  true  number  of  years 
from  the  Annunciation  or  from  the  Nativity.  And  also 
*  historical  chronology '  was  a  technical  term  for  the 
Christian  era  used  with  Julian  years  before  the 
Gregorian  Keformation,  which  identified  vulgar  chro- 
nology with  it,  so  that  my  present  use  is,  in  fact,  the 
original  use  of  the  term. 

Royal  Institution,  ALBE^LVRLE  Street,  London  : 
April  2,  1904. 


CO  J. 2 


M  o  t"  ri 

O    g    CC  J 
!=£  ^  *:!   * 


rH  C<J 


'    cc   ^   ;->   ^' 


.p^ 


?^"5  g  S  S 


<D    t?    c3 


So5 


tH  O  rH  ^ 


"<1 


O   c3 


O 
rH  O  tH 


e3   e8 


«8   S   ^ 


o  o 


«  K  «<  § 
cq  T-H  th  ^ 


a  00 

c3CO 


c3    "^ 


^  -^ 


o§ 


CM  CO  -^  CO 

o  o  o  o 


O  O 


ASTEONOMICAL 

AND 

HISTOEICAL   GHEONOLOGY 


Astronomers  call  the  year  which  immediately  pre- 
ceded 1  A.D.  the  year  0 ;  but  in  historical  chronology 
that  epoch  year  of  the  astronomical  system  is  called 
1  B.C. 

The  purpose  I  have  before  me  is  to  show  reason  for 
such  a  reformation  of  historical  chronology  as  to  bring 
it  into  accordance  with  the  method  of  numbering  the 
years  B.C.  which  has  been  adopted  by  astronomers. 

Besides  the  question  as  regards  the  method  of 
using  figures  for  numbering  the  years,  there  is  a  minor 
difference  between  astronomical  and  vulgar  reckoning 
due  to  the  astronomical  days  commencing  at  noon 
twelve  hours  after  the  commencement  of  the  day  by 
vulgar  reckoning.  As  regards  that  minor  difference, 
Sir  John  Herschel  has  advocated  a  reform  of  the 
astronomical  method  for  the  purpose  of  making  it 
agree  with  the  vulgar  method ;  and  if  the  astronomical 
world  to  whom  he  appealed  should  decide  on  that 
reform  jointly  with  the  reform  of  historical  chronology 
which  is  the  subject  of  this  paper,  then  the  two  methods 


8  ASTRONOMICAL  AND 

of  reckoning  would  agree  as  regards  the  enumeration 
of  both  days  and  years. 

Sir  John  Herschel,  being  himself  an  astronomer, 
fully  recognised  the  inconvenience  which  would  be 
caused  by  having  to  record  astronomical  observations 
for  the  same  night  under  two  different  dates,  but  he 
nevertheless  declared  uniformity  of  nomenclature  and 
modes  of  reckoning  to  be  of  such  vast  and  paramount 
importance  as  to  outweigh  every  consideration  of 
technical  convenience  or  custom.^ 

The  impracticability  of  changing  vulgar  chronology 
on  that  point  makes  a  reformation  of  the  astronomical 
system,  as  regards  it,  the  only  way  of  arriving  at 
uniformity. 

That  reform,  suggested  by  Sir  John  Herschel,  is, 
however,  a  distinct  and  subordinate  question  ;  and  that 
which  I  advocate  can  be  more  easily  effected,  and  is,  in 
fact,  quite  independent  of  the  reform  suggested  by  Sir 
John  Herschel. 

My  argument  will  be  found  to  be  to  the  effect  that 
the  astronomical  method  of  placing  a  zero  year  between 
the  B.C.  and  the  a.d.  years  is  intrinsically  superior  to 
the  historical  system,  which  places  1  B.C.  and  1  a.d.  in 
juxtaposition;  and  that,  in  fact,  when  the  existing 
enumeration  of  the  years  of  the  Christian  era  was 
arranged  the  year  which  is  now  the  zero  year  of 
astronomers  was  regarded  as  the  first  or  epoch  year  of 
the  era,  and  the  enumeration  of  1  a.d.  was  purposely 
given  to  what  was  then  recognised  as  the  second  year 
of  the  era.  And,  therefore,  when  astronomers  found  it 
expedient  to  push  back  the  numbers  of  the  B.C.  years,  by 

'  Outlines  of  Astronomy,  p.  87,  1849.     (London  :  Longmans.) 


HISTOEICAL  CHRONOLOGY  9 

treating  as  zero  what  had  become  in  historical  chrono- 
logy 1  B.C.,  they  unconsciously  re- adopted  the  enumera- 
tion of  years  B.C.  which  was  originally  adopted  tacitly, 
if  not  explicitly,  by  the  Benedictine  monks  who  founded 
the  era. 

My  argument  shows  that  through  a  misunder- 
standing on  the  part  of  comparatively  modern 
historians  they  treated  as  1  B.C.  the  year  which  when 
the  era  was  first  established  was  called  1  a.d.  by  those 
who  used  ordinal,  and  the  year  0  by  those  who  used 
cardinal,  numbers  ;  and  that  the  manner  in  which  the 
centuries  are  now  generally  considered  to  be  divided  is 
therefore  erroneous. 

For  an  exposition  of  the  questions  involved  histori- 
cally and  scientifically  in  this  subject  some  brief 
references  to  the  writings  of  Sir  John  Herschel^ 
Dr.  Lardner,  and  some  others,  will  suffice  not  only  to 
represent  what  have  been  prevalent  ideas,  but  also  to 
create  a  basis  for  the  establishment  of  some  facts  of 
which  they  appear  to  have  had  no  knowledge. 

Herschel  says  that  '  in  the  historical  dating  of  events 
there  is  no  a.d.  0.  The  year  immediately  previous  to 
A.D.  1  is  always  called  B.C.  1 ' ;  and  the  years  '  are 
denominated  as  years  current  {not  as  years  elapsed) 
from  the  midnight  between  December  31  and  Jami- 
ary  1  immediately  subsequent  to  the  birth  of  Christ.'  ^ 

He  further  says  that  '  the  designation  of  a  year 
by  A.D.  or  B.C.  is  to  be  regarded  as  the  name  of  that  year, 
and  7iot  as  a  mere  number  uninterruptedly  designating 
the  place  of  the  year  in  the  scale  of  time.'    He  says  :  *  The 

*  Outlines  of  Astronomy,  by  Sir  John  Herschel,  pp.  628,  629.     1849. 
(London.) 


10  ASTRONOMICAL  AND 

scale  of  A.D.  and  B.C.  is  not  continuous,  the  year  0  in 
both  being  wanting  ;  so  that  (supposing  the  vulgar 
reckoning  correct)  our  Saviour  was  born  the  year 
B.C.  i;  • 

Dr.  Lardner  says  that  1  a.d.  is  the  year  of  Kome 
754  ;  and  that  '  the  first  year  of  the  Christian  era  is 
not,  as  might  be  imagined,  that  of  the  birth  of  Christ, 
but  the  following  year.  It  is  the  year  in  which, 
according  to  Dionysius  Exiguus,  Christ  completed  his 
first  year.'  ^ 

Though  Dr.  Lardner  is  correct  in  those  statements, 
they  nevertheless  show  that  he  did  not  know  that 
before  the  Gregorian  Reformation  the  ordinal  numbers 
applied  to  the  years  by  Dionysius  were  discarded  for 
cardinal  numbers,  so  that  1  a.d.  became  apphed  to  what 
was  recognised  by  the  advocates  of  both  systems  to  be 
the  second  year  of  the  era  and  had  in  fact  been  called 

2  A.D. 

^According  to  the  Benedictine  records,  Dionysius 
did  not  make  the  mistake  of  calling  the  year  of  Rome 
753  the  year  1  B.C.  That  error  has  been  introduced 
subsequently  by  others  not  so  conversant  as  he  was 
with  what  were  then  supposed  to  be,  and  were 
accepted  as,  the  facts  of  the  case.  What  Dionysius 
called  1  A.D.  began  on  March  25,  753  of  Rome,  and 
ended  with  March  24,  754  of  Rome,^  and  his  method 
was  adopted   in  Pisa,  while  at  Florence  and   by    St. 

'  Outlines  of  Astronomy,  by  Sir  .John  Herschel,  p.  6o6.  1849. 
(London.) 

-  Common  Things  Explained,  by  Dr.  Dionysius  Lardner.  1856. 
(London.)     TJie  Almanack,  p.  6. 

'  L'Art  de  Verifier  les  Dates,  par  un  Religieux  Benedictin  de  la 
Congregation  de  S.  Maur  ;  vol.  i.  p.  v.,  troisierue  Edition.    1783.    (Paris.) 


HISTORICAL  CHRONOLOGY  11 

Augustine  in  England  the  following  year  was  called 
1  A.D.  The  Benedictines  record  that  position  of  the 
question  as  indisputable,  and  it  is  confirmed  by  the 
fact  that  in  the  twelfth  century  our  present  method  of 
calling  the  year  of  Rome  754  the  year  1  a.d.  did  not 
universally  prevail  even  among  those  who  used  for 
the  new  era  the  Julian  year  commencing  on  January  1, 
in  conformity  with  the  year  of  Rome.  By  them  the 
years  of  our  era  were  numbered  so  as  to  make  the  year 
of  Rome  753  identical  with  the  year  1  of  our  era,  so  that 
the  same  year  which  we  call  1102  a.d.  was  by  them  called 
1103  A.D.*  They  did  not  change  the  day  for  the  com- 
mencement of  the  year,  but  merely  substituted  1  a.d. 
for  753  A.u.c.  It  is  not  any  dijfference  of  opinion  as  to 
which  is  the  epoch  year  of  the  era,  but  merely  the 
difference  between  using  cardinal  instead  of  ordinal 
numbers  that  has  changed  the  above-mentioned  date 
from  A.D.  1103  to  1102 ;  and  a  peculiarity  of  the 
position  is  that  in  consequence  of  the  epoch  year 
having  become  erroneously  called  1  B.C.  the  cardinal 
numbers  used  by  the  Florentines  are  now  supposed  to 
be  ordinal  numbers,  as  stated  by  Sir  John  Herschel, 
whereas  in  fact  it  was  those  who  differed  from  the 
Florentine  method  of  applying  figures  to  the  years 
who  used  ordinal  numbers,  while  those  who  followed 
the  Florentine  enumeration,  which  has  become 
universal,  used  the  figures  as  cardinal  numbers.  If  the 
Dionysian  enumeration  had  been  maintained  the  present 
year  would  have  been  a.d.  1901,  but  the  substitution 
of  the  Florentine  method  has  made  it  a.d.  1900.- 

*  L'Art  de  Verifier  les  Dates,  pp.  iv,  viii,  and  ix. 
2  See  Preface. 


12  ASTRONOMICAL  AND 

The  records  of  which  I  shall  now  give  some 
examples  place  the  historical  accuracy  of  the  fore- 
going beyond  the  reach  of  dispute. 

The  two  phrases  Atmo  ah  Incarnatione  Dom'uii  and 
Anno  Incarnationis  Dominlccc  seem  to  have  been  used 
at  times  promiscuously  before  the  abbreviation  a.d. 
came  into  use ;  but  they  clearly  represented  originally 
the  two  different  systems  of  numbering  the  years,  the 
former  being  used  with  the  cardinal  and  the  latter 
with  the  ordinal  numbers. 

A  charter  signed  by  King  Kobert  II.  of  France, 
dated  '  Anno  Dominicae  Incarnationis  Mxxviii,'  is  shown 
to  belong  to  the  year  1027  a.d.  according  to  the  now 
prevailing  method  of  numbering  the  years. ^ 

Another  charter  signed  by  the  same  king,  dated 
*  Anno  Incarnati  Verbi  millesimo,'  is  shown  to  belong  to 
the  year  999  a.p.^  according  to  the  Florentine  system, 
which  has  now  completely  displaced  the  ordinal  enu- 
meration used  by  Dionysius. 

And  the  date  of  King  Kobert's  death,  which 
occurred  on  July  20,  1031  a.d.,  is  recorded  by  the 
historian  Helgaud  as  '  Anno  qui  est  Incarnationis 
millesimus  tricesimus  secundus.'  ^  That  clearly  declares 
what  we  call  1031  a.d.  to  be  the  1032nd  year  of  the  era. 

A  Strasbourg  date  is  recorded  as  *  Anno  Incarna- 
tionis Dominicae  milesimo  quinto,'  and  is  shown  to  be 
apphcable  to  the  year  1004  according  to  our  present 
system  ^ ;  and  it  has  been  therefore  inferred  that  the 
document  must  have  been  signed  between  Christmas 
Day  and  January  1,  between  which  dates  there  was 

'  UArt  dc  Verifier  les  Dates,  p.  v.  -  Ibid. 

^  Ibid.  *  Ibid.  p.  ix. 


HISTOEICAL  CHEONOLOGY  13 

often  confusion  as  to  which  year  was  current.  But, 
whatever  may  have  been  the  fact  in  that  special  case, 
it  seems  clear  that  such  a  date  as  Anno  Incarnationis 
Dominicae  quinto,  used  under  the  Pisan  system,  was 
originally  recognised  as  equivalent  to  Anno  ab  Incar- 
natione  Domini  quatuor  (not  quinque)  used  under 
the  Florentine  system ;  the  ordinal  number  quinto 
designating  the  same  year  as  the  cardinal  number 
quatuor. 

A  charter  signed  in  a  monastery  near  Eeims,  and 
dated  '  anno  Domini,  secundum  cursum  Ecclesiae 
Eemensis  Mcccxc,  decima  tertia  die  mensis  Junii,'  is 
shown  to  belong  to  the  year  1389  a.d.  by  our  record. 

King  John's  submission  to  Pope  Innocent  III.  is 
dated  '  on  the  third  day  of  October  in  the  year  from 
the  incarnation  Mccxiii.,'  ^  and  the  number  of  the 
year  accords  with  the  Florentine  system,  which  has 
always  prevailed  in  England. 

A  charter  granted  by  Athelberht,  King  of  Kent,  and 
with  the  granting  of  which  St.  Augustine,  then  Arch- 
bishop of  Canterbury,  appears  to  have  been  connected, 
is  dated  '  in  the  City  of  Canterbury,  anno  ab  Incarna- 
tione  Christi,  DCV.^  In  the  absence  of  any  suggestion 
to  the  contrary,  I  presume  that  the  enumeration  of  the 
year  605  accords  with  our  present  usage. 

The  Benedictine  work  from  which  I  have  already 
quoted  does  not  mention  any  use  of  the  Pisan  enumera- 
tion in  England ;  it  says  (p.  x.)  :  '  Le  calcul  Pisan, 
qui  precede  d'une  annee  entiere  celui  de  Florence,  a 

'  Arbuthnot,  Tlie  Mysteries  of  Chronology,  p.  49. 
2  Rules  for  Verifying  Dates,  by  John  J.  Bond,  Assistant  Keeper  in 
her  Majesty's  Record  Office.     1875.     (London.) 


14  ASTRONOMICAL  AND 

ete  en  usage,  non  seulement  a  Pise,  mais  a  Lucques,  a 
Sienne,  a  Lodi ;  plusieurs  Papes  s'y  sont  conformes 
dans  les  dates  de  leurs  Bulles,  et  plusieurs  Erapereurs 
d'Occident,  des  le  IX''  siecle,  dans  celles  de  leurs 
diplomes.*  They  have,  however,  as  above  shov^n,  proved 
its  use  in  France. 

Dr.  Lardner  says :  '  Dionysius  made  historical  re- 
searches, the  result  of  which  assigned  the  birth  of  Christ 
to  the  25th  day  of  December,  in  the  753rd  year  from 
the  foundation  of  Kome ' ;  it  appears  to  me,  however, 
quite  clear  that  Dionysius  deliberately  preferred  to 
make  the  era  commence  with  the  first  year  of  one  of  his 
cycles  of  582  years  (consisting  of  twenty-eight  lunar 
cycles  of  nineteen  years)  rather  than  with  the  records 
which  he  must  have  known  make  4  B.C.  of  the  vulgar 
era  the  first  year.  Bond,^  after  pointing  out  that  the 
Golden  Number  1  of  the  Dionysian  reckoning  falls  to 
the  year  known  as  1  B.C.,  says  :  '  But  as  that  year 
did  not  come  within  the  range  of  the  Roman  reckon- 
ing, the  number  1  of  the  first  cycle  of  532  years 
was  represented  by  0.'  And  then  he  adds :  *  Hence 
arose  a  system  by  which  the  annus  verus,  or  4  B.C., 
was  called  by  ecclesiastical  writers  8  B.C.,  by  the 
omission  of  1  B.C.  marked  0,  and  thus  great  confusion 
has  been  caused  when  calculations  have  been  made 
subject  to  that  erroneous  system.' 

I  do  not  know  what  authority  Bond  has  for  the 
fact  of  the  zero  year  having  been  used  as  he  states,  but 
I  have  no  doubt  as  to  the  accuracy  of  any  such  state- 
ments in  his  valuable  work  ;  the  tenour  of  my  argument 
is,  however,  all  to  the  effect  that  he  has  not  properly 

•  Rules  for  Verifying  Dates,  George  Bell  &  Sons,  1875,  p.  321. 


HISTORICAL  CHRONOLOGY  15 

appreciated  the  action  of  those  who  used  it  as  he 
states.  His  alhision  to  the  comments  on  the  absence 
of  a  year  0  which  were  made  by  Sir  John  Herschel 
(who  evidently  did  not  know  of  such  an  enumeration 
ever  having  been  used)  show  that  he  considers  the 
method  adopted  by  astronomers  to  be  an  erroneous 
system  of  enumeration,  and  make  it  appear  to  me 
that  he  misunderstood  the  object  of  Herschel's  com- 
ments. 

In  the  article  on  Chronology  in  the  '  Encyclopaedia 
Britannica  '^  W.  L.  K.  Gates  makes  some  contradic- 
tory statements.  He  says  the  Christian  era  commenced 
on  January  1  in  the  753rd  year  from  the  foundation  of 
Kome,  meaning,  I  presume,  753  a.u.c,  as,  though  753rd 
might  be  applied  to  752,  it  cannot  be  applied  to  754, 
A.u.c,  which  corresponds  with  1  a.d.,  and,  so  interpreted, 
that  statement  agrees  with  the  further  statement  he 
makes  (in  direct  contradiction  to  Herschel)  to  the 
effect  that  the  years  of  the  Christian  era  are  distin- 
guished by  the  cardinal  numbers.  He,  however,  not 
only  does  not  comment  on  the  fact  that  those  state- 
ments make  the  year  1  a.d.  the  second  year  of  the  era, 
and  are  incompatible  with  the  application  of  the  name 
1  B.C.  to  the  year  of  Kome  753,  but  also  he  himself 
further  on  treats  1  a.d.  as  the  first  of  our  era  and  the 
preceding  year  as  1  B.C.,  regardless  of  the  fact  that 
those  statements  directly  contradict  his  previous  state- 
ments that  the  numbers  are  cardinal  and  that  1  a.d. 
commenced  with  the  753rd  year  of  Eome.  His  state- 
ment that  the  era  commenced  on  January  1  of  the 
4714th  year  of  the  Julian  period  also  makes  1  a.d.  the 

*  Ninth  edition,  vol.  v.  p.  712. 


16  ASTRONOMICAL  AND 

first  of  the  era.    The   '  Encyclopaedia '     truly  reflects 
the  confusion  of  ideas  which  has  existed. 

The  fact  is  that  the  Gregorian  Keformation  has 
virtually  made  the  era  commence  with  January  1, 
753  of  Home,  reverting  to  the  method  of  those  who, 
as  already  stated,  applied  the  term  '  year  of  the  Incar- 
nation '  to  the  years  of  Kome  commencing  on  Janu- 
ary 1,  treating  the  first  year  of  the  Incarnation  as  the 
year  753  of  Eome,  on  the  same  principle  as  a  year  a.d. 
might  be  referred  to  as  the  first  of  a  king's  reign  and 
the  following  year  a.d.  as  the  second  of  his  reign,  so 
that  he  might  be  recorded  as  in  the  second  j^ear  of  his 
reign  after  reigning  a  few  months,  or  even  a  few  days.^ 
By  reverting  to  that  principle  the  Gregorian  Keforma- 
tion got  rid  of  the  confusion  created  by  the  change 
from  the  Julian  to  the  Christian  year.  But  that  was 
not  the  commencement  of  the  year  in  the  *  year  of  the 
Incarnation,'  which  was  the  original  Christian  era,  and 
was  introduced  into  England  by  St.  Augustine  in  the 
sixth  centmy,  soon  after  its  invention  by  Dionysius  ^ ; 
but  St.  Augustine  appears  to  have  used  it  with  the 
Florentine  instead  of  the  Dionysian  enumeration.  It 
was,  I  understand,  considered  to  commence  with  what 
is  now  termed  Lady  Day,  or  the  Feast  of  the  Annun- 
ciation, March  25  of  the  year  of  Eome  753.  At 
any  rate,  Dionysius  called  the  year  commencing  on  that 
date  the  year  1,  and  St.  Augustine's  introduction  of  the 
Florentine  enumeration  into  this  country  resulted  in  the 

'  '  Elagabalus  reigned  three  years  and  nine  months  of  solar  years,  and 
yet  we  have  coins  dated  in  his  fifth  year.'  Bond,  Rules  for  Verifying 
Dates,  1875,  p.  23. 

2  L*Art  de  Verifier  les  Dates,  vol.  i.  p.  iii. 


HISTOEICAL  CHEONOLOGY  17 

year  1  a.d.  becoming  recognised  as  commencing  on  March 
25,  754  A.u.c.  Statements  by  accurate  authorities  are 
sometimes  apparently  contradictory  merely  in  conse- 
quence of  two  different  years  being  used  at  the  same 
time  in  the  same  country,  so  that  both  may  be  true 
though  each  ignores  the  existence  of  the  system  differ- 
ing from  that  recorded  by  him.  According  to  Bond's 
1866  edition  of  the  work  quoted  on  page  14,  the  year 
of  the  Nativity  was  in  use  in  England  at  the  time 
of  the  Norman  Conquest,  and  the  Julian  year  was 
then  introduced  by  "William  I.  and  continued  to  be 
used  for  about  100  years,  when  Henry  II.  substituted 
the  year  of  the  Incarnation.  His  1875  edition,  how- 
ever, recognises  the  latter  year  as  having  been  the 
first  used  in  England,  and  the  French  work  I  have 
quoted  is  very  explicit  as  to  the  years  of  the  original 
era  of  the  Incarnation  having  commenced  on  March 
25  .;  and  adds  that  after  a.d.  744  and  the  time  of 
Charlemagne  French  historians  who  used  the  years 
of  Jesus  Christ  did  not  all  agree  as  to  the  commence- 
ment of  the  year.  It  is  also  pointed  out  that  Gregory 
of  Tours  confounded  the  era  of  the  Incarnation  with 
that  of  the  Passion,  and  that  is  perhaps  the  original 
source  of  much  subsequent  confusion.  The  year  of 
the  Nativity  appears  by  the  French  work  (p.  x)  to  have 
been  first  used  in  England  in  the  seventh  century. 
And,  in  the  thirteenth  century,  Gervais  of  Canterbury 
asserted  that  it  had  been  used  by  nearly  all  English 
writers  who  had  preceded  him  *  pour  la  raison  que  ce 
jour  est  comme  le  terme  ou  le  soleil  finit  sa  course  et  la 
recommence.'  The  general  tenour  of  the  Benedictine 
work  shows   them   to   have   considered   it   clear   that 

B 


18  ASTRONOMICAL  AND 

(except  some  adherence  to  the  Julian  year)  no  year 
but  that  of  the  Incarnation  was  used  with  the  vulgar 
Christian  era  until  some  time  after  the  date  of  its 
introduction  into  England.  The  question  as  to 
whether  St.  Augustine  used  the  year  of  the  Nativity 
or  that  of  the  Incarnation  is  not,  however,  material  to 
my  main  argument.  St.  Augustine  was  a  Benedictine, 
and  was  educated  by  Gregory  I.  before  the  latter 
became  Pope.  Gregory,  however,  does  not  appear  to 
have  used  the  Christian  era  at  all,  as  the  first  recorded 
use  of  it  by  any  of  the  Popes  is  in  613  a.d.  by 
Boniface  IV.,  fifteen  years  after  St.  Augustine's  arrival 
in  England,  and  whatever  may  be  proved  to  be  the 
method  adopted  by  either  will  probably  have  been  the 
one  used  by  the  other.  As  St.  Augustine  was  a  Benedic- 
tine, it  seems  natural  that  he  should  have  used  the  year 
of  the  Incarnation  commencing  on  March  25,  but  it  is 
remarkable  that  the  Pisan  enumeration  had  apparently 
been  abandoned  by  him  in  favour  of  the  Florentine. 

In  connection  with  the  foregoing  argument  it  is 
expedient  to  record  that  the  most  recent  of  writers  on 
chronology,  F.  F.  Arbuthnot,^  on  the  authority  of 
Father  Hardouin,  expresses  doubts  as  to  any  such 
person  as  Dionysius  Exiguus  having  existed ;  but 
the  fact  of  the  invention  of  the  Christian  era  remains 
indisputable,  and  no  reason  is  shown  why  the  Bene- 
dictine traditions  should  not  have  handed  down  the 
name  of  the  originator  of  the  era.  If  the  legend  of 
Dionysius  is  rejected,  it  can  only  be  said  that  the 
era  was  invented  by  some  Benedictine  monks  whose 

'  The  Mysteries  of  Chronology,  by  F.  F.  Arbuthnot,  pp.  18-22.  1900. 
(London.) 


HISTOEICAL  CHRONOLOGY  19 

names  have  not  been  handed  down  to  posterity,  and  the 
foregoing  argument  remains  unaffected ;  for  if  Dionysius 
is  not  the  name  of  an  individual  who  made  a  special 
study  of  the  subject,  it  serves  the  pm-pose  of  repre- 
senting the  group  of  Benedictines  who  originated  the 
era. 

Arbuthnot,  like  Herschel,  Lardner,  Playfair,  and 
others,  treats  the  year  1  a.d.  as  the  first  year  of  our 
era  ^ ;  but  the  erroneous  name,  1  B.C.,  given  to  the  year 
of  Kome  753,  which  immediately  precedes  it,  seems  to 
be  the  only  reason  for  doing  so.  Having  treated  the 
year  753  of  Rome  as  1  B.C.,  they  could  not  logically 
regard  the  year  next  following  it  as  the  second  of  the 
Christian  era,  though  the  *  Encyclopaedia  Britannica,' 
as  above  shown,  disregards  logic  in  the  question ;  for, 
as  already  shown,  it  declares  the  figures  we  use  to  be 
cardinal  numbers,  and  that  the  year  753  A.u.c.  is  the 
first  of  our  era,  directly  contradicting  Herschel  on 
those  two  points,  but  it  immediately  afterwards  joins 
with  Herschel  by  treating  1  a.d.  as  the  first  of  the  era 
and  declaring  the  preceding  year  to  be  1  B.C.,  thus 
making  both  those  figures  ordinal  numbers  and 
making  753  a.u.c.  the  same  as  1  B.C. 

In  *  Macmillan's  Magazine '  for  February,  1900,  a 
writer  signing  '  Dionysius  Minimus '  says  that  he  finds 
it  recorded,  on  the  authority  of  the  Astronomer  Royal, 
that  it  has  been  agreed  in  chronology  to  call  the  first 
year  of  the  Christian  era  1  a.d.  ;  and  that  it  also 
appears  that  there  are  in  existence  two  letters  of  Dio- 
nysius which  prove  that  arrangement  to  have  been 
his  deliberate  intention  ;  but  the  facts  I  have  recorded 
*  The  Mysteries  of  Chrofwlogy,  p.  7  ;  see  also  pp.  16,  17. 

b2 


20  ASTEONOMICAL  AND 

above  show  that  though  it  is  true  that  Dionysius 
called  the  first  year  of  the  era  1  a.d.,  the  year  so 
named  by  him  is  that  which  became  in  vulgar 
chronology  called  1  B.C.,  and  what  the  Florentines 
called  1  A.D.  was  called  by  him  2  a.d.  We  apply  to 
the  years  of  the  era  the  same  figures  as  the  Florentines 
applied  to  them  respectively,  but  we  erroneously  treat 
them  as  ordinal  numbers,  though  the  figures  applied 
by  Dionysius,  which  really  represented  the  ordinal 
numbers,  were  always  one  figure  in  advance  of  the 
Florentine  figures,  which  latter  are  the  figures  of  all 
our  now  existing  records  of  dates. 

A  question  which  must  force  itself  upon  the  atten- 
tion of  anyone  who  considers  the  foregoing  circum- 
stances is  as  to  why  (excepting  the  minor  difference  as 
to  commencing  at  noon  or  at  midnight)  there  should 
be  any  difference  between  astronomers  and  other 
chronologers  in  the  system  of  recording  historically 
the  dates  of  events.  It  certainly  cannot  be  disputed  that 
the  astronomical  system  is  a  reasonable  and  correct 
method.  If  by  that  method  an  event  occurred  in  the 
year  100  B.C.  and  another  event  on  the  corresponding 
day  in  the  year  ]  00  a.d.,  the  lapse  of  time  between  them 
is  200  years;  whereas  under  the  vulgar  system  one 
year  must  be  deducted  after  adding  the  dates  together 
to  get  the  correct  number  of  years  between  the  two 
events.  So  also  for  reckoning  leap  years  the  same 
rules  apply  under  the  astronomical  system  for  the 
dates  B.C.  as  for  those  A.D.  ;  whereas  under  the  vulgar 
system  the  rules  which  apply  to  the  dates  a.d.  do  not 
apply  to  those  B.C.  On  the  other  hand,  the  vulgar 
method  does  not  seem  to  have  any  advantage  over  the 


HISTOEICAL  CHKONOLOGY  21 

astronomical  method.     Why  should  that  confusion  of 
systems  be  persisted  in  ? 

The  authorities  who  established  the  era  treated  it 
as  if  they  supposed  Christ  to  have  been  born  in  the 
year  of  Kome  753,  and,  therefore,  in  treating  that  as 
the  epoch  year  of  the  scale  of  time,  and  numbering  it  the 
year  0,  and  the  year  preceding  that  1  B.C.,  astronomers 
merely  comply  with  what  were  accepted  as  historical 
facts  when  the  era  was  adopted. 

Admitting  that  the  year  of  Kome  753  is  not  really 
the  year  in  which  Christ  was  born,  but  that  it  is 
expedient  to  adhere  to  the  date  which  was  accepted  for 
the  establishment  of  the  epoch  based  on  that  event 
when  the  era  was  invented,  the  year  of  Eome  752, 
which  is  in  vulgar  chronology  called  the  year  2  B.C.,  is 
correctly  called  by  astronomers  1  B.C. ;  and  the  year  of 
Kome  753,  which  in  vulgar  chronology  is  called  1  B.C., 
is  the  epoch  year  of  the  Christian  era,  and  is  correctly 
called  by  astronomers  the  year  0. 

A  misconception  of  the  principles  on  which  an 
epoch  for  the  record  of  events  ought  to  be  based  seems 
to  be  the  only  explanation  for  the  epoch  year  having 
been  omitted  when  historians  first  numbered  the  B.C. 
years  in  vulgar  chronology ;  and  its  omission  creates 
an  error  in  the  record  of  time  identical  with  that  which 
would  be  created  by  the  omission  of  the  unit  cipher 
between  the  teens  and  the  twenties  or  between  the 
twenties  and  the  thirties.  By  passing  from  29  to  31, 
ignoring  the  cipher  of  the  thirties,  a  correction,  by 
deducting  one  year  from  every  date,  would  for  ever 
afterwards  be  necessary  to  get  a  true  record  of  years 
elapsed  ;  and  the  cipher  year  of  the  forties  would  have 


22  ASTRONOMICAL  AND 

to  be  reckoned  as  belonging  to  the  thirties  in  order  to 
keep  the  ten-year  periods  equal,  though  in  the  absence 
of  the  erroneous  omission  of  the  year  30  the  year  40 
would  arithmetically  belong  to  the  series  of  the  forties, 
because  it  would  signify  that  forty  years  of  the  era  had 
elapsed,  not  that  the  40th  year  was  current.  The 
error  appears  to  be  due  to  the  consecutive  framers  of 
the  vulgar  era,  as  now  constituted,  not  having  always 
recognised  that  a  zero  year  is  requisite  for  its  com- 
mencement, to  divide  the  a.d.  from  the  B.C.  years,  just 
as  a  zero  is  arithmetically  requisite  between  each 
separate  group  of  integral  units.  That  error  is  avoided 
by  astronomers  and  was  not  made  by  those  who 
gave  to  the  a.d.  years  the  numbers  now^  in  use,  but 
was  made  subsequently  by  those  who  numl^ered  the 
B.C.  years.  To  use  Sir  John  Herschel's  phrase, 
chronologers  have  been  driven  to  the  expedient  of 
'calHng  the  years  names,'  instead  of  counting  them 
mathematically,  in  consequence  of  the  erroneous 
omission  of  the  zero  year  between  the  B.C.  and  the 
A.D.  years. 

Sir  John  Herschel  says,  in  one  of  the  above  extracts, 
that  the  year  0  is  wanting  in  the  a.d.  as  well  as  in  the 
B.C.  part  of  the  scale  of  years.  The  fact,  however,  is 
that  it  is  because  we  do  not  know  where  the  true 
origin  is  that  we  have  to  create  a  fictitious  origin  ;  and 
it  would  be  as  great  a  mistake  to  constitute  two  zero 
years,  one  for  the  B.C.  scale  and  another  for  the  a.d. 
scale,  as  that  made  by  the  total  omission  of  the  zero 
year  in  vulgar  chronology.  The  astronomical  scale  as 
at  present  constituted  is  all  one  scale  with  a  perfect 
arithmetical   sequence  throughout ;    the  years  in  one 


HISTORICAL  CHRONOLOGY  23 

direction  from  zero  being  virtually  ^j/?/.s,  and  those  in 
the  other  direction  minus  quantities  ;  and  the  arithme- 
tical sequence  is  not  affected  by  the  position  selected 
for  the  zero.  The  zero  of  astronomers  is  in  fact  the 
zero  year  of  time  transferred  to  an  artificial  position 
arbitrarily  determined  ;  and  wherever  placed  it  is  the 
zero  of  all  years,  whether  B.C.  or  a.d.  The  year  of 
Rome  753  was  the  chosen  epoch  year  when  our  era 
was  founded,  and  it  properly  belongs  to  the  first 
century  of  the  era  based  upon  it  wherever  that  century 
may  be  in  the  absolute  scale  of  time  ;  so  that  the  year 
of  Rome  853  was  the  first  year  of  the  second  century 
of  our  era,  not  the  last  of  the  first  century.  The 
calling  of  the  year  of  Rome  753  the  year  1  B.C.  after 
having  made  1  a.d.  represent  the  year  of  Rome  754 
is  an  error  to  which  astronomers  cannot  reasonably 
conform,  as  that  number  arithmetically  belongs  to 
the  year  of  Rome  752,  and  is  correctly  appHed  to  it  by 
astronomers  ;  and  as  we  are  now  (November  1900)  in 
the  year  of  Rome  2653,  we  are  therefore  in  the  first 
year  of  the  twentieth  century  of  years  in  the  Christian 
era.  If  the  year  of  Rome  753  really  were  the  year 
1  B.C.,  as  in  vulgar  chronology  it  is  now  erro- 
neously called,  then  we  should  not  be  in  the  twentieth 
century  of  the  Christian  era  until  next  year  (a.d.  1901) 
commences. 

It  is  because  Sir  John  Herschel  makes  the  Chris- 
tian era  commence  with  the  year  following  what 
historians  call  the  year  1  B.C.  that  he  says,  as  above 
stated,  that  the  dates  represent  years  current,  not  years 
elapsed.  But  as  that  year  is  properly  treated  by 
astronomers  as  the  year  0,  and  is  in  fact  the  epoch 


24  ASTEONOMICAL  AND 

year  of  the  Christian  era,  the  numbers  as  at  present 
appHed  to  the  years  A.D.  do  in  fact  represent  years 
elapsed  in  the  Christian  era,  not  years  current,  as 
declared  by  Herschel  on  the  supposition  that  the 
erroneous  name  1  B.C.  given  by  modern  historians  to 
the  epoch  year  puts  that  year  out  of  the  era. 

Avowedly  knowing  the  year  of  Kome  753  to  be 
determined  on  for  the  epoch  year  of  the  vulgar  era,  in 
contradistinction  to  what  must  have  been  known  to  be 
the  true  era,  the  Florentines  seem  to  have  delibe- 
rately rejected  the  enumeration  of  1  a.d.  which  had 
been  appHed  to  it  under  the  Pisan  system,  and  to  have 
termed  the  year  of  Kome  754  the  year  1  a.d.,  because 
in  cardinal  enumeration  the  first  year  of  the  era  is  the 
zero  of  years,  and  the  second  5^ear  is  the  first  in  which 
a  complete  unit  of  years  can  be  counted.  At  any  rate, 
the  adoption  of  their  method  by  modern  astronomers 
shows  that  they  took  the  correct  course  in  fixing  1  a.d., 
and  the  further  evidence  I  have  cited  shows  that 
though  Dionysius  used  ordinal  numbers  to  represent 
the  years  of  the  era,  that  method  was  gradually 
rejected  in  favour  of  cardinal  numbers,  making  what 
was  recognised  as  the  second  year  of  the  era  1  a.d. 

It  is  mere  matter  of  fact  that  the  ordinal  enumera- 
tion, first,  second,  third,  &c.,  does  not  correspond  with 
the  common  arithmetical  (or  cardinal)  enumeration, 
one,  tw^o,  three,  &c.,  respectively,  but  with  the  arith- 
metical index  figures,  0,  1,  2,  &c.,  respectively.  The 
arithmetical  index  figure  1  cannot  appear  in  the  scale 
of  time  in  which  years  are  the  units,  until  what  is  in 
ordinal  enumeration  the  first  year  is  passed. 

Though  the  idea  of  treating  zero  as  a  number  does 


HISTOEICAL  CHEONOLOGY  25 

not  appear  to  have  been  entertained  by  ancient  mathe- 
maticians,^ 0  is  now  acknowledged  to  be  the  first 
number,  and  is,  therefore,  also  the  first  figure  in 
arithmetic,  and  9  is  the  10th. 

Confusion  has  been  created  by  the  imperfect  or 
contradictory  ideas  of  enumeration  which  formerly 
prevailed.  Archimedes  represents  the  numbers  1  to  9  by 
letters  of  the  Greek  alphabet,  but  does  not  give  a  letter 
to  represent  zero.  It  is  only  more  recently  that  the 
cipher  was  brought  into  arithmetic  as  a  tenth  figure ; 
and  still  more  recently  mathematicians  have  realised 
the  fact  that  zero  must  be  regarded  as  a  7iumher  ;  and 
its  acceptance  as  such  gives  the  cipher,  which  was 
previously  treated  as  the  tenth  figure,  the  position  of 
the  first  number,  and,  therefore,  that  of  the  first  figure, 
and  makes  the  position  of  tenth  figure  still  given  to  it 
in  text-books  a  survival  from  the  erroneous  theory 
which  formerly  excluded  zero  from  the  category  of 
numbers. 

Sir  John  Herschel's  remarks  show  that  he  recog- 
nised that  in  vulgar  chronology  the  years  are  now 
considered  to  be  reckoned  by  ordinal  numbers,  both 
B.C.  and  A.D.,  and  that  such  a  system  is  unsuitable  for 
the  measurement  of  time.  But  his  comment  as  to  the 
absence  of  a  year  0  in  the  A.D.  scale  shows  that  he 
supposed  that  though  the  years  B.C.  are  reckoned  in  the 
astronomical  scale  by  cardinal  numbers  representing 
years  elapsed  (counting  backwards),  those  of  the  a.d. 
scale  are  reckoned  in  ordinal  numbers  representing 
years  current.  He  evidently  regarded  the  a.d,  and  the 
B.C.  years  as  belonging  to  two  separate  scales.  But 
'  Century  Dictionary. 


26  ASTRONOMICAL  AND 

the  astronomical  scale  of  time  is  in  fact  all  one 
continuous  scale,  and  as  such  cannot  have  more  than 
one  zero  year  upon  it.  It  would,  as  above  said,  be  as 
great  a  mistake  to  put  in  two  zero  years  as  to  leave  the 
zero  out  altogether. 

A  foot  rule  measures  the  same  distance  whether  it 
is  turned  with  the  enumeration  of  the  inches  running 
from  left  to  right  or  from  right  to  left.  Suppose,  for 
the  sake  of  illustration  (the  epoch  inch,  like  the  epoch 
year  in  the  astronomical  scale,  being  treated  as  zero), 
the  beginning  of  time  to  be  found  at  any  point  of  time 
—say,  exactly  at  4713  B.C.  (the  moment  that  figure 
leaves  the  vulgar  scale  as  an  ordinal  number  and  ap- 
pears on  the  astronomical  scale  as  a  cardinal  number). 
Then  the  B.C.  part  of  the  scale  might  be  inverted; 
and  the  zero  year  of  the  Christian  era  w^ould  take  its 
proper  place  as  the  zero  year  of  the  complete  scale  of 
time,  the  number  4713  being  substituted  in  its  place  so 
that  4714  would  remain  identical  with  1  a.d.,  and,  as 
at  present  numbered,  the  a.d.  years,  at  any  date,  added 
to  the  B.C.  period  of  4713  years  would  give  the  correct 
measure  on  the  scale  of  time  ;  but  to  do  so  the  numbers, 
both  A.D.  and  B.C.,  must  of  necessity  represent  cardinal 
numbers  recording  years  elapsed,  not  years  current. 
The  year  0,  which  was  the  enumeration  of  the  first 
year  of  the  old  era,  continues  to  be  that  of  the  first 
year  of  the  new  era.  It  is  the  zero  of  all  years 
wherever  it  may  be  placed.  If  a  second  zero  year  had 
been  added  specially  for  the  a.d.  part  of  the  scale  then 
the  present  numbers  would  be  pushed  forwards,  1  a.d. 
taking  the  place  of  2  a.d.,  and  the  mistake  made  by 
the  insertion  of  the  second  zero  year  w^ould  have  to  be 


HISTOKICAL  CHRONOLOGY  27 

corrected  by  always  adding  one  year  to  the  date  to  get 
the  true  position  on  the  scale  of  time. 

The  admission  of  a  single  zero  year  makes  the 
figures  in  both  directions  from  it  cardinal  numbers  and 
the  absence  of  a  zero  year,  as  in  the  vulgar  scale,  makes 
them  ordinal  numbers  in  both  directions.  Those 
ordinal  numbers  were  rejected  by  the  Florentines  ;  and 
not  only  have  modern  astronomers  re-adopted  the 
Florentine  system,  but  also  Sir  John  Herschel  ex- 
pressly declares  ordinal  numbers  to  be  unsuitable  for 
the  scale  of  time. 

As  a  question  of  pure  theory  the  astronomical 
system  is  the  only  correct  method  of  recording  time  on 
a  single  scale.  One  zero  year  only  can  appear  on  the 
scale,  and  that  must  of  necessity  be  the  first  year  of 
the  era ;  the  years  which  follow  it  being  plus  quantities 
and  those  which  precede  it  minus  quantities.  The 
difference  between  plus  one  year  and  minus  one 
year  is  two  years,  which  is  correctly  shown  in  the 
astronomical  scale  ;  but  the  vulgar  scale  makes  the 
difference  only  one  year  instead  of  two  years,  and 
the  suggested  additional  zero  year  for  the  a.d.  years 
would  make  such  a  scale  show^  a  difference  of  three 
years  instead  of  two  years.  I  must  repeat  that  not 
only  does  theory  require  the  first  year  of  any  era  to  be 
enumerated  by  the  index  figure  0,  but  also  the  year  0 
of  astronomers  is  in  fact  the  original  epoch  year  of  our 
era,  and  as  such  was  numbered  by  Dionysius  the  year 
1  as  he  used  ordinal  enumeration,  and  the  figures  as 
now  applied  in  the  subsequent  cardinal  enumeration  of 
the  years  a.d.  do  in  fact  represent  years  elapsed,  not 
years  current. 


28  ASTRONOMICAL  AND 

Though  not  material  to  the  main  purpose  of  my 
argument,  it  is  nevertheless  of  interest  to  record  the 
opinions  of  leading  authorities  as  to  what  was  the 
date  of  the  birth  of  Christ. 

Some  students  of  the  question  argue  that  a  con- 
junction of  the  planets  Jupiter  and  Saturn  which 
occurred  in  the  year  of  Kome  747  (the  vulgar  7  B.C., 
or  astronomical  6  B.C.)  formed  the  Star  of  Bethlehem, 
and  thus  make  that  the  true  epoch  year ;  while  others 
suggest  that  the  first  of  two  comets  recorded  by 
Chinese  astronomers  in  the  years  of  Kome  749  and  750 
respectively  makes  the  first  of  those  two  years  the  true 
date,  which  by  the  astronomical  record  would  be  4  B.C. 
or  by  the  vulgar  record  5  B.C.  This  latter  is  the  date 
accepted  by  James  Play f air.  ^  He,  however,  alludes 
to  it  as  '  about  four  years  prior  to  the  date  of  the 
vulgar  Christian  era,'  -  professing  himself  unable  to 
decide  as  to  whether  the  event  occurred  towards  the 
end  of  748  or  in  the  middle  of  749  of  the  years  of 
Rome.  His  argument  is  to  the  effect  that  an  eclipse 
of  the  moon  which  occurred  on  March  13,  4  B.C.  (astro- 
nomical 3  B.C.)  fixes  that  year,  which  is  750  a.u.c,  as 
the  date  of  the  death  of  King  Herod  the  Great ;  and 
that  '  it  is  highly  probable  '  that  Christ  was  born  '  not 
much  more  than  a  year  before  Herod's  death.' 

Playfair  incidentally  refers  to  Dionysius  as  having 
'  adjusted '  the  first  year  of  the  Christian  era  to  the 

'  A  System  of  Chrcynologij,  by  James  Playfair,  D.D.  Edinburgh,  p.  2G0. 
1784. 

-  Ibid.  p.  50.  The  '  era  of  Jesus  Christ '  was  at  one  time  used  with 
the  numeration  commencing  with  4  b.c.  of  the  Vulgar  era,  thus  agreeing 
with  Playfair's  argument. 


HISTOKICAL  CHEONOLOGY  29 

4714th  of  the  Julian  period/  though  the  fact  is  that 
the  so-called  Julian  period  or  cycle  was  invented  by 
Scaliger  (as  Playfair  of  course  knew)  only  in  the  year 
1582  A.D.  (the  year  of  the  Gregorian  Keformation)  for 
the  concordance  of  various  cycles  of  which  it  is  a 
common  measure,  and  March  25,  4713  (not  4714)  of 
the  Julian  period  corresponds  with  the  commencement 
of  the  year  1  as  fixed  by  Dionysius.  If,  as  stated  by 
Playfair,  Dionysius  invented  the  Christian  era  about 
the  year  527  a.d.,  his  so-called  adjustment  was  with 
the  years  of  Kome ;  and  March  25,  527  a.d.  (termed 
by  him  the  528th  year  of  the  era)  was  March  25, 
1280  of  Kome ;  but  his  work  was  not  one  of  adjust- 
ment, but  of  disturbance,  for  he  took  the  above  date 
instead  of  January  1  as  the  commencement  of  the 
year.  The  adjustment  was  effected  by  the  Gregorian 
Reformation  (in  1582  a.d.),  which  made  the  year  1280 
of  the  Roman  era  (A.u.c,  or  Anno  Urbis  Conditae) 
identical  with  527  a.d.  by  making  the  Christian  years 
commence,  like  the  Julian  years  (which  were  the  years 
of  the  Roman  era)  on  January  1. 

Playfair  also  refers  to  the  Incarnation  as  if  repre- 
senting our  Christmas  Day  instead  of  our  Lady  Day, 
and  that  confusion  of  the  origin  of  the  era  of  the 
Incarnation  seems  to  have  become  general.  The  Bene- 
dictines say  of  the  year  : 

*  Plusieurs  la  commen9oient  sept  jours  plutot  que 
nous,  et  donnoient  pour  le  premier  jour  de  I'annee  le 
25  Decembre,  qui  est  celui  de  la  naissance  du  Sauveur. 
D'autres  remontoient  jusqu'au  25  Mars,  jour  de  la 
Conception,  ou   de  son  Incarnation  dans   le   sein   de 

'  A  System  of  Chronology y  p.  50. 


30  ASTRONOMICAL  AND 

la  Yierge,  coinmuncment  appele  le  jour  de  TAnnoii- 
ciation.'  ^ 

The  year  4  B.C.  of  vulgar  reckoning  is  now 
generally  accepted  as  the  date  of  the  birth  of  Christ, 
though  according  to  the  researches  of  Playfair  just 
mentioned  it  may  have  been  5  B.C.,  or  perhaps  6  B.C. 
The  framers  of  the  vulgar  era  must  (as  I  have 
already  stated)  have  knov^n  at  least  as  well  as  we  now 
do  what  was  the  true  era  if  commenced  from  the  birth  of 
Christ.  That  generally  accepted  date,  4  B.C.  vulgar  or 
3  B.C.  astronomical,  makes  the  year  1900  the  fourth  year 
of  the  twentieth  century  of  years  from  the  date  of  that 
event  ;  for  if  we  counted  from  that  year,  treating  it  as 
the  epoch  year,  and  the  year  which  follows  it  as  1  a.d., 
the  year  1900  would  be  counted  as  1903,  or  the  1904th 
year  of  the  era.  And  if  the  Dionysian  estimate, 
which  brings  the  event  nearer  than  any  other  to  our 
time  and  forms  the  basis  on  which  the  era  was 
founded,  be  accepted  subject  to  the  Gregorian  Eeforma- 
tion,  nineteen  complete  centuries  of  years  had  elapsed 
in  the  era  when  the  year  1900  commenced,  making 
that  year  therefore  the  first  in  the  twentieth  century. 

It  must  of  course  be  borne  in  mind  that  every  new 
era  which  has  been  invented  has  given  to  all  preceding 
events  dates  which  were  unknown  when  the  events 
occurred.  An  eclipse  of  the  moon  which  occurred  in 
the  year  of  Rome  w^hich  Dionysius  supposed  to  be 
that  of  the  Incarnation  and  of  the  birth  of  Christ  is  now 
recorded  as  having  ocdirred  on  January  11  of  the  year 
0  of  the  astronomical  scale,  which  is  identical  with  the 
year  of  Rome  753  excepting  the  difference  of  six  hours 

'  L\irt  dc  Verifier  les  Dates,  p.  iv. 


HISTOKICAL  CHRONOLOGY  31 

which  Herschel  has  suggested  ought  to  be  reformed  in 
the  astronomical  scale.  Since  the  commencement  of 
that  year  a  complete  cycle  of  the  seasons,  winter, 
spring,  summer,  and  autumn,  had  occurred  1900 
times  when  the  month  of  January  1900  commenced ; 
and  we  therefore,  on  January  1,  1900,  entered  on  the 
twentieth  century  of  cycles  of  the  seasons  in  the 
Christian  era  according  to  both  the  Florentine  (or  St. 
Augustine)  and  the  Pisan  (or  Dionysian)  methods  of 
counting  combined  with  the  Gregorian  Reformation, 
which  made  the  Pisan  year  1  and  the  Florentine  0 
identical  with  the  year  753  A.u.c. 

Twice  since  the  foundation  of  the  Second  Baby- 
lonian Empire  by  Nabonassar,  who  reformed  the 
previous  chronological  system  with  the  assistance 
of  Egyptian  astronomers,  the  vulgar  record  of  years 
has  been  subjected  to  further  reformation  for  the  pur- 
pose of  correcting  its  divergence  from  the  true  record 
of  the  seasons.  The  year  of  Nabonassar,  consisting  of 
exactly  365  days,  was  used  in  the  era  of  the  Eomans 
until  the  time  of  Julius  Caesar,  when,  in  order  to 
correct  an  accumulated  error  due  to  the  vulgar  years 
being  shorter  than  true  years,  Caesar  ordered  that  the 
year  of  Rome  708  should  last  for  445  days,  making  the 
year  709  commence  with  the  first  new  moon  which 
occurred  after  the  winter  solstice  of  the  previous  year ; 
and  the  intercalation  of  days  was  so  arranged  as  to 
make  January  1,  709  A.u.c,  coincide  with  that  new 
moon.^     At  the  same  time,  to  prevent  a  recurrence  of 

*  Bond,  on  pp.  322-323  of  his  1875  edition  already  quoted  from, 
gives  a  table  of  corresponding  years  of  the  Julian  era  and  the  years  of 
Borne.     His  table,  however,  ignores  the  years  of  the  Roman  era  as 


32  ASTRONOMICAL  AND 

the  error  which  was  corrected  as  above  shown,  Caesar, 
under  the  guidance  of  Sosigenes  of  Alexandria,  ordered 
that  every  fourth  year  should  consist  of  366  days,  so  as 
to  make  the  average  length  of  the  year  365^  days ;  but 
whereas  the  year  of  Nabonassar  is  nearly  a  quarter  of 
a  day  shorter  than  a  true  year,  the  Julian  year  of  365 
days  and  6  hours  is  slightly  longer  than  a  true  year,  the 
length  of  the  astronomical  year  on  which  the  seasons 
depend  being  365  days  5  hours  48  minutes  and  46 
seconds  approximately.  Caesar  and  Sosigenes  doubtless 
knew  their  year  to  be  inexact,  but  considered  that  the 
necessary  correction  might  be  trusted  to  the  intelli- 
gence of  future  statesmen  who  might  be  in  possession 
of  more  accurate  knowledge  for  their  guidance  ;  and 
that  expectation  was  somewhat  tardily  justified  by  the 
action  of  Pope  Gregory  XIII.,  who  in  the  year  1582  a.d. 
ordered  that  October  5  should  be  treated  as  the  15th, 
thus  shortening  that  year  ten  days  to  correct  the 
amount  by  which  the  years  since  the  Julian  Eeforma- 
tion  had  been  too  long  to  keep  time  exactly  with  the 
earth's  revolution  round  the  sun.  That  reformation, 
then  effected  wherever  the  authority  of  the  Pope  pre- 
vailed, was  not  effected  in  England  until  the  year 
1752  A.D.,  by  which  time  the  error  had  increased  to 
eleven    days,    to    remedy   which    September    3   was 

reformed  by  Csesar ;  and  it  therefore  shows  that  after  the  Julian  Reforma- 
tion three  systems  were  used  by  Rome — namely,  the  old  style  of  the 
era  of  Rome,  the  reformed  era  of  Rome,  and  the  Julian  era  dating 
from  the  Julian  Reformation.  It  is  immaterial  to  my  argument  whether 
it  be  based  on  the  eras  with  their  years  coinciding,  as  arranged  by  the 
Julian  and  Gregorian  Reformations,  or  on  the  old  style  Roman  years, 
commencing  on  April  21,  and  the  Julian  years  of  the  Christian  era, 
commencing  on  January  ]  allowance  being  made  for  the  overlapping  of 
the  years  of  the  two  eras. 


HISTORICAL  CHRONOLOGY  33 

ordered  to  be  called  the  14th.  To  prevent  a  recurrence 
of  the  error  then  corrected  it  was  ordered  that  three 
times  in  each  400  years  a  year  which,  under  the  unre- 
formed  Julian  Calendar,  would  be  a  leap  year  of  366 
days  should  be  a  common  year  of  365  days  ;  but  the 
rigid  working  of  the  Julian  Calendar  in  accordance 
with  the  Gregorian  Keformation  still  creates  an  error 
of  one  day  in  about  3,000  years,  for  the  correction  of 
which  one  of  the  years  which  under  the  Gregorian  rule 
would  be  a  leap  year  will  doubtless  be  ordered  by  the 
authorities  of  the  time  to  be  treated  as  a  common  year. 
The  excess  in  the  length  of  the  reformed  Julian  year, 
which  is  now  the  vulgar  or  civil  year,  amounts  to 
about  2  days  14  hours  and  24  minutes  in  10,000  years. 
In  a  paper  on  '  The  Secular  Acceleration  of  the 
Moon's  Motion  '  which  I  pubHshed  in  the  year  1879 
I  alluded  to  the  absence  of  any  common  measure  be- 
tween days  and  years  as  being  due  to  the  fact  that 
the  motions  which  they  respectively  measure  are  due 
to  the  interaction  of  two  independent  forces — the  sun's 
and  the  earth's  revolving  force — whose  relative  quan- 
tities not  only  have  no  necessary  mathematical  pro- 
portion, but  have  a  ratio  which  is  subject  to  a  slowly 
progressive  change  which  is  at  present  beyond  the 
grasp  of  mathematical  knowledge. 

As  a  matter  of  detail,  it  must  be  observed  that  between 
the  introduction  of  the  era  of  the  Incarnation  into 
England  by  St.  Augustine  and  the  final  restoration  of 
the  Julian  year,  many  changes  occurred  in  England.  Not 
only  did  usage  change  between  the  use  of  the  years  of  the 
three  eras — the  Incarnation,  the  Nativity,  and  the  Julian 
— but    civil    and    ecclesiastical  courts   used   different 

c 


34  ASTRONOMICAL  AND 

eras  at  the  same  time.  The  change  from  March  25  to 
January  1  for  the  commencement  of  the  year,  effected 
by  the  Gregorian  Keformation,  merely  corrected  the 
distm'bance  caused  by  the  temporary  adoption  of  the 
years  specially  adapted,  sometimes  to  one  and  at  other 
times  to  the  other  of  the  two  above-mentioned  Christian 
eras,  and  restored  the  general  use  of  the  Julian  year, 
which  does  not  appear  ever  to  have  gone  completely 
out  of  use. 

It  must  also  be  observed  that  the  error  by  which 
the  Christian  era  has  been  made  to  commence  with  the 
beginning  of  the  year  1  a.d.,  instead  of  treating 
the  first  day  of  that  year  as  the  first  anniversary  of  the 
commencement  of  the  era,  is  also  made  in  naming  the 
years  of  the  ScaHger  cycle,  commonly  called  the  Julian 
Period,  of  7980  years  (in  which  the  year  4718  of  the 
current  cycle  corresponds  with  the  year  0  of  the 
astronomical  scale),  the  enumeration  of  the  years  in 
that  cycle  being  made  in  ordinal  numbers  because  the 
error  seems  to  have  been  made  in  every  then  existing 
era  except  the  original  Florentine,  and  when  the 
Scaliger  cycle  was  invented  the  Florentine  figures 
were  erroneously  supposed  to  represent  ordinal  numbers. 
The  original  Florentine  system  is  in  fact  the  present 
astronomical  system  of  treating  the  Christian  era  as 
above  interpreted,  and  is  the  only  scale  of  time  that 
has  ever  been  clearly  organised  on  a  correct  mathema- 
tical basis. 

The  disturbance  of  the  Julian  years,  sometimes  by 
those  of  the  era  of  the  Incarnation  and  at  other  times 
by  those  of  the  era  of  the  Nativity,  was  due  to  narrow- 
minded  views  of  the  subject  which  created  confusion 


HISTORICAL  CHRONOLOGY  35 

throughout  our  historical  records  for  more  than  a 
thousand  years  until  corrected  by  our  adoption  of  the 
Gregorian  Eeformation. 

The  Julian  year,  then  legaHsed,  does  not  appear 
ever  to  have  been  completely  out  of  use.  It  was  used 
by  the  kings  of  England  in  the  eleventh  and  twelfth 
centuries ;  and  was  afterwards  used  as  the  '  historical 
year '  to  distinguish  it  from  the  year  of  the  Incar- 
nation re-introduced  by  Henry  II ;  and  the  documents 
of  the  Venetian  State  Library  copied  by  Kawdon 
Brown  show  that  in  the  fifteen  century,  more  than 
a  hundred  years  before  the  Gregorian  Eeformation,  the 
Popes  of  Rome  were,  in  the  months  of  January  and 
February,  one  year  in  advance  of  the  kings  of 
England  in  dating  their  letters,  as  would  be  the  case  if, 
while  the  kings  of  England  were  using  the  years  of 
the  Incarnation,  the  Popes  of  Rome  were  using  the 
Julian  years. ^  Bond,  however  (in  agreement  with 
other  chronologers) ,  states  that  the  year  of  the  Nativity 
was  at  that  time  used  in  Rome,  and  in  that  case 
(which  also  accords  with  the  recorded  letters)  then  the 
Popes  must  have  been  using  the  year  of  the  Nativity 
with  the  Pisan  enumeration  while  the  kings  of 
England  were  using  the  years  of  the  Incarnation  with 
the  Florentine.  Among  numerous  protests  in  London 
of  bills  of  exchange  drawn  in  Venice  there  is  one 
dated  *on  the  31st  of  December,  1442  (Anglican 
Style),  "  secundum  cursum  et  computacionem  Ecclesiae 

'  Calendar  of  State  Papers  and  Manuscripts  relating  to  English 
affairs  existing  in  the  Archives  and  Collectio^is  of  Venice,  and  in  other 
Libraries  of  Northern  Italy.  Edited  by  Rawdon  Brown,  published  by 
the  Lords  Commissioners  of  the  Treasury.  Vol.  i.  pp.  134,  135,  &c. 
1864. 

c  2 


36  ASTEONOMICAL  AND 

Anglicanae  "  '  :  i  and  I  see  no  reasonable  explanation 
for  such  a  specification  of  the  date  except  on  the  suppo- 
sition that  the  year  1443  a.d.  (not  1442)  was  then  the 
legal  enumeration  of  the  year,  which  had  to  be  distin- 
guished from  that  legally  current  in  England.  That 
accords  with  the  idea  of  the  English  enumeration 
having  originally  been  cardinal  and  that  used  in  some 
parts  of  Italy  ordinal.  The  general  tenour  of  the 
admitted  historical  facts  bearing  on  the  question  seems 
to  allow  of  no  other  explanation  for  the  enumeration 
of  the  years  of  the  Nativity  (commencing  on  December 
25)  having  been  such  as  to  make  them  precede  that 
of  the  years  of  the  Aimunciation  (commencing  on 
March  25).  And  the  evidence  is,  therefore,  to  the 
effect  that  the  difference  of  one  complete  year  in  the 
enumeration  of  the  Christian  era  which  at  one  time 
existed,  as  pointed  out  in  '  L'Art  de  Verifier  les  Dates,' 
was  in  the  first  instance  reduced  to  a  difference  of  three 
months  by  the  years  of  the  Nativity  being  used  with 
the  Pisan  enumeration  while  the  years  of  the  Incar- 
nation were  used  with  the  Florentine  enumeration  ; 
that  a  second  approximation  was  made,  reducing 
the  difference  seven  days  further,  by  changing  the 
Pisan  method  in  Eome  from  the  years  of  the  Nativity 
to  the  Julian  years ;  and  that  the  third,  and  final,  step 
was  made  by  those  who  used  the  Florentine  enumera- 
tion changing  from  the  years  of  the  Incarnation  to 
the  Julian  years.  That  seems  to  me  to  be  clearly 
the  course  through  which  the  discrepancy  of  one 
year  disappeared,  and  to  leave  no  doubt  as  to  the  Pisan 

'  Calendar  of  State  Papers  and  Mami scripts,  dx.     Vol.  ii.  p.  568. 
1807. 


HISTOEICAL  CHKONOLOGY  37 

enumeration  having  originally  been   ordinal  and   the 
Florentine  enumeration  cardinal. 

As  a  matter  of  detail  it  is,  however,  appropriate  to 
point  out  that  the  despatches  of  the  Venetian  am- 
bassadors to  foreign  Courts  show  that  at  the  time  of 
the  Gregorian  Keformation  (1582)  they  were  using  a 
year  commencing  on  March  1  (not  25),  so  that  in 
the  months  of  January  and  February  they  dated  one 
year  less  than  the  date  of  the  Julian  year  established 
by  the  reformation,  but  all  through  March  their  dating 
corresponded  with  the  established  JuHan  year.^  They 
were  perhaps  also  distinguishing  their  dates  from  those 
of  the  years  of  the  Nativity,  but  the  dates  of  some  of 
the  letters  are  at  variance  with  the  extension  of  the 
difference  over  the  intervening  seven  days.  There  is  a 
letter  from  Lorenzo  Priuli,  Venetian  Ambassador  in 
France,  which  he  dates  :  '  Paris,  11th  January  1581 
(m.v.),'  to  distinguish  the  year  from  1582,  then  presum- 
ably current  in  Eome.  But  there  is  another  letter 
of  his,  preceding  the  above,  dated :  '  Paris,  28th  De- 
cember 1581,'  as  if  the  year  1582  had  commenced 
in  the  rival  enumeration  (not  on  December  25)  but 
between  the  dates  of  the  two  letters.  The  evidence 
is  to  the  effect  that  the  Julian  year  had  been 
substituted  for  that  of  the  Nativity  before  the  Gre- 
gorian Keformation  was  decreed,  the  Bull  being  dated 
February  24, 1582,  which  was  then  1581  by  the  English 
reckoning. 

The  relation  which  I  have  described  between  the 
Pisan  and  Florentine  systems  makes  it  of  interest  to 

'  Caleiidar  of  State  Papers  and  Maiiuscripts  dx.    Edited  by  Horatio 
F.  Brown,  vol.  viii.  p.  27,  &c.     1894. 


38  ASTEONOMICAL  AND 

notice  that  Bond,  under  the  heading '  The  Era  of  Pisa,' 
says  :  *  This  era  differed  from  our  common  Christian 
era  only  by  preceding  it  by  one  year ;  probably  the 
first  year  of  the  Christian  era  was  made  to  correspond 
to  753  A.u.c.  instead  of  754  a.u.c,  the  Dionysian 
date.' ' 

The  fact  certainly  is  that  it  was  by  the  Gregorian 
Keformation  that  the  year  1  of  the  original  *  era  of 
Pisa  '  was  made  to  correspond  with  753  A.u.c,  while  at 
the  same  time  the  year  1  of  the  era  of  Florence  was 
made  to  correspond  with  754  a.u.c,  as  (subject  to 
various  changes  in  both  '  eras  '  between  years  of  the 
Nativity,  years  of  the  Incarnation,  and  Julian  years) 
the  '  era  of  Pisa '  was  used  in  Kome  and  the  era  of 
Florence  in  England  and  Venice  until  the  adoption  of 
the  Gregorian  Keformation  in  all  three  places  merged 
the  two  '  eras '  into  one.  There  is  certainly  no  more 
reason  for  treating  the  era  of  Pisa  independently  than 
for  dealing  in  the  same  manner  with  the  era  of 
Florence.  The  Pisan  appears  to  have  been  the 
original,  and  to  have  always  been  used  in  Kome ;  and 
the  Florentine,  which  became  adopted  in  England  and 
Venice,  was  merely  an  attempt  to  change  the  Pisan 
method  of  enumerating  the  years  without  any  inten- 
tion of  changing  the  epoch,  or  date  for  the  origin  of 
the  era.  The  Florentines,  in  fact,  anticipated  the  course 
which  has  since  virtually  been  adopted  by  astronomers  ; 
but  the  Pisan  and  Florentine  systems  were  merely 
different  methods  of  enumerating  the  years  of  the 
same  era. 

To  account  for  the  discrepancy  between  the  vulgar 

'  p.  225,  1875  edition. 


HISTORICAL  CHRONOLOGY  39 

Christian  era  and  the  true  era  Bond  ^  supposes  Dionysius 
to  have  been  misled  through  treating  the  '  era  of 
Augustus  '  as  commencing  four  years  later  than  its  true 
date ;  but  the  object  of  Dionysius  is  said  to  have  been 
to  substitute  for  the  era  of  Diocletian  (or  the  era  of 
martyrs),  then  chiefly  used  among  Christians,  an  era 
dating  '  ab  Incarnatione  D.  N.  Jesu  Christi '  ^ ;  and,  in 
the  absence  of  any  definite  proof  of  his  having  made 
the  mistake  with  which  he  is  commonly  discredited, 
it  appears  to  me  incredible  that  he  was  not  fully 
acquainted,  not  only  with  the  era  of  mart3TS,  but  also 
with  the  *  era  of  Christ,'  which  was  then  a  well-known 
era  also  used  among  Christians  ;  and,  if  so,  he  must 
have  discarded  what  was  accepted  as  the  true  era,  not 
for  the  sake  of  correcting  any  historical  error,  but  for 
what  he  considered  the  advantage  of  making  it  com- 
mence with  some  period  in  the  lunar  cycle  which 
regulated  the  Church  festivals,  in  the  organisation  of 
which  he  was  an  expert. 

Bond  treats  as  the  true  date  of  the  birth  of  Christ 
December  25,  750  a.u.c,  which  was  the  first  day  of  the 
first  year  in  the  '  era  of  Christ ' ;  and  Dionysius  appears 
to  have  substituted  March  25  of  the  year  753  A.u.c. 
(not  754,  as  supposed  by  Bond).  March  25,  which  my 
argument  makes  the  epoch  fixed  on  by  Dionysius, 
belongs  to  753  a.u.c.  Jahan  style ;  to  752  A.u.c.  old 
style ;  to  45  of  the  JuHan  era  ;  and  to  4713  of  the 
Scaliger  cycle,  commonly  called  the  Julian  period. 
The   question,  therefore,  is   as   to   whether  the  lunar 

1  p.  X  of  his  1875  edition. 

2  Dictionary  of  Christian  Biography,  edited  by  William  Smith  and 
Henry  Wace. 


40 


ASTKONOMICAL  AND 


•S  +>  '^  aJ 

C  tic  CO    9} 

•2  =   ?^ 

S  5  as 
12; 


X  bo 

Oi        C    r/3  O 

u    £  2 

^      cJ  «  C 


^     «»  be"© 
^       §,■§§ 

o  01  j: 


\c 


S     St  S  d 


I  1^ 

!    O 


be 
i    ^ 


S2SS^Si2"=S5S^g^S^^S;^'^ 

as 

COfNCOOOOOt-OWS'^JOfMi-iOCftXt-OiO 

Cycle 
used 
in      , 
Saxon 
Charters 
accord- 
ing to  • 
Bond 

XVII. 
XVIII. 
XIX. 

I. 

11. 

III.  1 

IV.  ; 
V.  i 

VI.  1 

VII.  i 

VIII. 

IX. 

X. 

XI. 

XII.  i 

XIII.  1 

XIV.  1 
XV. 

XVI. 

,  Meton's 
i  Cycle 
'■  accord- 
ing to 
!  Bond 

• 

a.c  >.ia  a  o  »  o 
I   •''.2-^sg'tg? 


..S    85 


w  m  a^  -^  a  »  C 


X 


HISTORICAL  CHBONOLOGY  41 

cycle  shows  any  reason  for  the  selection  of  that  dale 
(not  for  any  date  in  the  year  754  A.u.c). 

Bond  says  :  '  To  find  the  number  of  the  Dionysian 
cycle  of  19  years,  add  I  to  the  given  year  of  the 
Christian  era  (because  number  II  belongs  to  1  a.d. 
according  to  the  Dionysian  system) ;  then  divide  the 
sum  by  19,  the  quotient  will  show  the  number  of  cycles 
elapsed  since  the  year  1  B.C.,  and  the  remainder  will 
represent  the  year  of  the  cycle.'  ^ 

As  the  enumeration  of  the  years  of  the  Metonic 
cycle  which  was  in  use  at  the  time  of  the  Dionysian 
Reformation  was  then  altered  for  the  special  purpose  of 
adjusting  them  to  the  new  era,  it  seems  natural  that 
number  1  should  be  applied  to  the  first  year  of  the  era ; 
and,  therefore,  the  above  statement  by  Bond  is  a 
confirmation  of  my  argument  to  the  effect  that  1  a.d. 
represents  the  second  (not  the  first)  year  of  the  era  as 
originally  organised.  And  as  the  enumeration  of  the 
years  of  the  Metonic  cycle  which  had  been  in  use  ever 
since  the  year  432  B.C.  had  been  changed  for  use  in  the 
Christian  Church  in  such  a  manner  that  Number  I  of 
the  cycle  corresponded  with  the  year  1  of  the  '  era  of 
Christ,'  the  question  is  as  to  whether  the  organisation 
of  the  calendar  shows  any  reason  for  combining  with 
a  change  from  the  years  of  the  Nativity  to  those  of  the 
Annunciation  a  change  of  three  years  in  the  *  golden 
numbers '  of  the  lunar  cycle  as  then  used  in  all 
Christian  Churches.  The  facts  of  the  case  appear  to 
me  to  make  it  evident  that  for  the  commencement  of 
the  year  the  date  of  the  Annunciation  was  preferred  to 
that  of  the   Nativity  on  account  of  the  dates  of  the 

'  P.  253,  1875  edition. 


42  ASTEONOMICAL  AND 

Church  festivals  being  determined  by  the  new  moon 
of  the  vernal  equinox  ;  and  that  the  year  753  A.u.c, 
Julian  style,  was  preferred  to  any  other  in  the  same 
lunar  cycle  because  the  calendar  new  moon  next 
preceding  that  equinox  occurs  closer  to  the  equinox 
than  in  any  other  year  of  the  cycle.  That  appears  to 
afford  a  still  further  confirmation  of  my  argument  to 
the  effect  that  Dionysius  considered  what  is  now 
1  A.D.  to  be  the  2nd  year  of  the  era.  The  calendar 
shows  no  reason  for  taking  anj^  year  marked  by  the 
golden  number  II  as  the  first  year  of  the  era. 

The  Dionysian  Eeformation  not  only  abandoned 
the  then  existing  era  of  Christ  commencing  on 
December  25,  750  a.u.c,  but  also  abandoned  the 
numbering  of  the  Metonic  cycle  based  on  that  era, 
and  applied  number  I  of  the  cycle  to  what  is  now 
erroneously  called  1  B.C.  instead  of  to  4  B.C.,  as  then 
numbered  for  the  original  *  era  of  Christ,'  which  com- 
menced on  Christmas  Day  of  the  year  4  B.C.  of  our 
vulgar  era. 

As  the  original  numbering  of  the  Metonic  cycle  as 
arranged  in  432  B.C.  had  in  fact  been  changed  in  such 
a  manner  that  Number  I  corresponded  with  the  year  1 
of  the  era  of  Christ,  Dionysius  and  those  who  acted 
with  him  must  have  had  a  thorough  practical  know- 
ledge of  it,  and  cannot  have  been  influenced  by  any 
historical  mistake  in  the  matter. 

It  is  important  to  observe  that  the  golden  number  I 
of  the  Metonic  cycle  which  Dionysius  discarded  did 
not  agree  with  the  year  1  of  the  era  of  martyrs,  but 
with  the  year  1  of  the  era  of  Christ,  so  that  if  he  had 
merely  wished  to  change  from  the  era  of  martyrs  to 


HISTOEICAL  CHEONOLOGY  43 

the  era  of  Christ  all  that  was  requisite  was  to  change 
the  enumeration  of  the  years  of  the  era  by  adding  287 
years  so  as  to  make  the  era  commence  in  the  year  of 
the  golden  number  I  as  then  applied  to  the  Metonic 
cycle  used  with  the  era  of  Christ ;  and  he  would  then 
have  had  for  the  epoch  of  the  era  what  he  must  have 
well  known  to  be  a  closer  approximation  to  the  true  date 
of  the  birth  of  Christ  than  that  which  he  adopted. 
That  is  so  because,  as  the  year  288  of  the  era  of 
Christ  commenced  in  the  year  1  of  the  era  of  martyrs, 
the  addition  of  287  years  to  the  latter  era  would  have 
made  the  enumeration  of  years  of  the  era  of  martyrs 
and  the  Golden  Number  I  of  the  era  of  Christ  coincide 
at  the  epoch  of  the  latter  era,  which  became  known 
as  the  annus  venis  in  contradistinction  to  the  vulgar 
epoch} 

'  Bond  (p.  X,  1875)  says  :  '  The  first  year  of  the  first  Dionysian 
Pascal  Cycle  of  532  years  '  was  '  1  Anno  Domini  with  golden  number  II 
of  the  Dionysian  Cycle.' 

That  statement,  however,  tends  to  create  confusion  in  three  distinct 
ways. 

First,  because  it  is  only  by  applying  the  Gregorian  reform  to  our 
golden  numbers  and  not  to  the  Pascal  Cycle  that  golden  number  I  and 
year  1  of  the  Pascal  Cycle  are  made  to  differ  at  all.  They  certainly 
coincided  when  Dionysius  framed  the  cycle  and  adopted  the  golden 
numbers. 

Secondly,  because  it  is  only  the  last  three  months  (less  seven  days)  of 
the  year  1  of  the  Pascal  Cycle  to  which  golden  number  II  can  in  any 
sense  be  applied. 

And,  thirdly,  because  the  enumeration  of  the  years  of  the  first 
Dionysian  Pascal  Cycle  of  532  years  is  in  fact  the  original  Dionysian 
enumeration  of  the  years  of  our  era,  being  identical  with  the  era  of  Pisa, 
which,  as  I  have  already  shown,  was  used  in  Kome,  while  the  era  of 
Florence  was  used  in  England. 

I  do  not  point  out  the  above  for  the  sake  of  being  hypercritical  regard- 
ing statements  which  suited  Bond's  immediate  purpose  in  verifying  dates, 


44  ASTRONOMICAL  AND 

It  must  also  be  observed  that  a  full  moon  more 
closely  precedes  December  25  in  the  golden  number  I 
of  the  Metonic  cycle  which  agreed  with  the  year  1  in 
the  era  of  Christ  than  in  any  other  year  of  the  cycle, 
whereas  August  29,  which  was  the  epoch  in  the  era  of 
martyrs,  has  no  definite  connection  with  the  lunar 
cycle.  The  evidence  is,  therefore,  to  the  effect  that 
the  true  era  of  Christ  (as  well  as  the  era  of  martyrs) 
was  deliberately  rejected  in  the  Dionysian  Eeformation 
for  the  sake  of  adopting  the  first  epoch  in  the  life  of 
Christ  which  best  suited  as  a  basis  for  the  regulation 
of  Church  festivals  as  then  organised.  And  it  seems 
also  probable  that  the  epoch  Christmas  Day  of  the  *  true 
era  of  Christ '  was  determined  as  much  by  the  dates  of 
calendar  full  moons  ^  in  the  Metonic  cycle  as  by  any 
accurate  knowledge  of  the  true  date  of  the  birth  of 
Christ.  It  can  only  be  said  to  be  more  nearly  true 
than  the  date  according  with  the  Dionysian  epoch. 

A  peculiarity  of  the  calendar  which  I  have  not  seen 
anywhere  mentioned,  is  that  the  approximate  dates  of 
the  new  moons  have  long  been,  and  will  for  many 
years  continue  to  be,  two  years  in  advance  of  the 
golden  number  to  which  the  present  dates  were  ad- 
justed in  the  Dionysian  cycle.  That  is  to  say,  the 
year  1900  is  quite  correctly  designated  in  the  almanac 

but  in  order  to  clear  apparent  clashing  between  some  of  his  statements 
and  my  arguments. 

'  Playfair,  in  his  table  of  eclipses  in  the  work  I  have  already  quoted 
on  p.  28,  records  an  eclipse  of  the  moon  as  having  occurred  on  March 
13,  4  B.C.,  and  full  moon  would  therefore  occur  on  December  3  of  that 
year  and  again  on  January  2,  3  b.c.  ;  so  thai  the  calendar  full  moon  of 
the  epoch  Christmas  Day  of  the  original  era  of  Christ  appears  to  have 
occurred  about  eight  days  before  the  real  full  moon. 


HISTORICAL  CHRONOLOGY  45 

as  being  golden  number  I.  of  the  cycle  ;  but  the  new 
moons  are  not  those  which  belong  to  number  I.,  but 
are  those  which  belong  to  number  III.  For  seven 
of  the  moons  the  calendar  date  is  the  same  as  that 
of  the  almanac  ;  and  for  the  other  five  moons  the 
greatest  discrepancy  is  less  than  twelve  hours,  which  is 
a  discrepancy  which  must  of  necessity  arise  in  the 
calendar  in  consequence  of  the  lunations  being  reckoned 
sometimes  as  twenty-nine  and  sometimes  thirty  days 
instead  of  in  accordance  w^ith  the  actual  change  in  the 
moon's  position.  The  table  which  I  have  given  on 
page  40  can  easily  be  compared  with  the  almanac 
for  many  years  to  come  for  verification  of  the  position 
of  the  real  moon  in  relation  to  that  of  the  calendar. 
That  table  gives  the  dates  of  calendar  new  moons  in 
the  line  of  the  golden  number  for  the  year,  and  the 
dates  of  real  new  moons  for  the  same  year  are  those  of 
the  calendar  new  moons  two  years  in  advance. 

For  about  twelve  moons  following  any  29th  day  of 
February,  the  almanac  date  will  usually  be  one  or  two 
days  less  than  the  present  amount  of  eight  days  in  advance 
of  the  calendar ;  and  then  the  discrepancy  will  again 
gradually  increase  until  another  leap  year  stops  the  moon's 
advance  in  the  almanac  by  pushing  the  enumeration 
of  days  forward  to  keep  pace  with  the  moon.  The 
mean  advance  between  two  successive  leap  years  does 
not  make  the  almanac  correctly  measure  astronomical 
time,  because  an  allowance  for  further  correction  must 
be  made  at  the  rate  of  2d.  14h.  24m.  in  10,000  5^ears 
(see  p.  33).  The  mean  difference  between  our  almanac 
measure  and  astronomical  measure  since  0  a.d.  now 
amounts  to  twelve  hours  ;  and  that  difference  will  go  on 


46  ASTRONOMICAL  AND 

increasing  until  one  of  the  years  which  the  calendar 
as  now  arranged  makes  a  leap  j'ear  is  treated  as  a 
common  year.  By  skipping  a  leap  year  now  the  dis- 
crepancy between  true  measure  and  almanac  measure 
since  the  epoch  of  our  era  would  not  be  corrected, 
but  approximately  reversed.  The  almanac  was  ad- 
justed to  the  moon  in  1582  A.D.,  but  the  above  cor- 
rection is  required  in  both  directions  from  that  date. 
It  ought  not,  however,  to  be  made  until  the  discre- 
pancy exceeds  half  a  day  in  relation  to  that  adjust- 
ment. 

The  reason  for  the  existing  position  of  the  moon  in 
relation  to  the  calendar  is  that  it  loses  2  hours  5 
minutes,  about,  in  each  cycle,  making  rather  more  than 
8  days  in  the  1900  years ;  ^  and  that  difference  chances 
to  bring  it  into  agreement  with  the  calendar  moons  of 
golden  number  III.  The  fact  that  the  discrepancy  of 
8  days  is  the  actual  difference  between  years  I.  and  III. 
of  the  cycle  appears  to  make  the  calendar  in  the  first 
year  of  the  era  agree  with  the  moon  ;  but  a  closer  in- 
spection shows  8  daj^s  to  be  the  maximum  and  5  days 

'  Playfair  (on  page  16)  makes  : 

19  years  =  6939d.  14h.  26m.  24^8.,  and 
235  months  =  6939     16     31        o" 

difference  0       2       4      35i 

And  the  relative  lengths  of  the  year  and  the  astronomical  month  now 
accepted  make  the  figures  : 

19  years  of  365d.  5h.  48m.  46s.  and  235  months  of  29-53059  days 
equal  respectively : 

6939d.  14h.  26m.  34s.,  and 
6939     16     31      3H 


difference  0  2  4  56| ;  and  the  secular  accelera- 
tion of  the  moon  makes  2h.  5m.  a  closer  approximation  ;  making  the 
difference  in  1900  years  =  8d.  16h.  20m.,  or  about  8"^  days. 


HISTORICAL  CHRONOLOGY  47 

the  minimum  advance  of  our  almanac  dates  on  those 
of  the  calendar  of  Table  II.  The  average  advance  on 
the  dates  as  they  stand  in  that  table  is  only  6  days 
17  hours,  vi^hich  does  not  agree  with  the  idea  of  its 
having  been  adjusted  to  the  moon,  either  at  the  com- 
mencement of  the  Christian  era  or  at  the  time  it  v^as 
brought  into  use.  The  moon  of  the  Church  calendar 
appears  to  have  become  quite  independent  of  the  real 
moon  before  Dionysius  reorganised  the  calendar,  and 
he  evidently  did  not  base  his  reform  on  what  was  then 
the  true  position  of  the  moon. 

The  evidence  is  to  the  effect  that  the  positions  of 
the  calendar  moons  as  they  stand  in  Table  II.  in  rela- 
tion to  the  golden  numbers  now  in  use  were  adjusted 
to  the  moon  about  three  centuries  after  the  com- 
mencement of  the  Christian  era ;  and  that  Dionysius, 
therefore,  must  have  brought  back  into  use  an  old 
calendar  without  attempting  to  make  it  conform  with 
the  changed  position  of  the  real  moon  in  relation  to  it. 

To  make  the  basis  of  argument  quite  clear,  I  may 
point  out  that  Sir  Harris  Nicolas  extracts  from  '  L'Art 
de  Verifier  les  Dates '  a  *  Perpetual  Lunar  Calendar  ' 
in  which  the  moons  placed  against  the  golden  numbers 
now  in  use  accord  with  what  I  have  given  on  page  40, 
but  he  says :  '  To  the  golden  number  which  was  used 
for  ascertaining  when  the  new  moons  occurred  for  the 
old  style,  epacts  have  succeeded  for  the  neiv.'  The 
dates  given  in  that  calendar  are,  however,  the  Dionysian 
calendar  moons  of  those  respective  golden  numbers  in 
the  new  style  ;  and  the  discrepancy  I  deal  with  is  the 
same  whether  the  argument  be  based  on  the  dates  of 
the  new  or  the  old  style  almanac,  correctly  extended 


48  ASTEONOMICAL  AND 

back  to  Meton's  time,  or  on  the  almanac  dates  of  Meton's 
time  correctly  extended  forwards  to  oar  time.  My 
argument  deals  only  with  the  dates  indicated  by  the 
*  Perpetual  Lunar  Calendar '  based  on  the  golden 
numbers  of  the  Metonic  cycle  and  the  natural  dis- 
crepancies between  those  calendar  moons  and  the  real 
moon.  I  am  not  concerned  with  the  artificial  arrange- 
ments for  corrections  organised  either  in  the  Dionysian 
or  in  the  Gregorian  calendar.  At  the  time  of  the 
Gregorian  Keformation  the  date  of  the  moon  indi- 
cated by  the  golden  number  was  about  seven  days 
before  that  of  the  real  moon,  but  the  corrections  in 
the  calendar  as  it  had  been  organised  had  actually 
made  the  calendar  moon  five  days  later  than  the  real 
moon.  The  extreme  discrepancy  that  can  arise  under 
the  new  style  is,  according  to  Nicolas,^  three  days  ; 
and  De  Morgan  considers  part  of  that  discrepancy  to 
have  been  purposelj^  organised  in  order  to  keep  Easter 
Day  from  coinciding  with  the  Passover. - 

Another  peculiarity  which  I  have  not  seen  alluded 
to  appears  only  when  it  is  recognised  that  before 
Dionysius  changed  the  positions  of  the  golden  numbers 

'  The  Chrmwlogy  of  History,  by  Sir  Harris  Nicolas,  K.C.M.G.,  p.  80. 
1833  (London  :  Longmans). 

-  '  On  the  P^cclesiastical  Calendar,'  pp.  18,  19,  &c.,  The  British 
Almanac,  1845.  De  Morgan  gives  the  following  quotation  from  Clavius, 
who  organised  the  new  calendar  :  '  If  the  moon  of  the  cycle  fell  on  the 
same  day  as  the  mean  new  moon  of  the  astronomers,  it  might  chance 
that  we  should  celebrate  Easter  on  the  same  day  as  the  Jews  or  the 
Quartodeciman  heretics,  which  would  be  absurd,  or  else  before  them, 
which  would  be  still  more  absurd.'  Clavius  seems  to  me  to  have  been 
in  advance  of  the  calendar  in  referring  to  the  time  the  Jews  '  celebrate 
Easter  ' ;  but  the  extract  makes  it  clear  that  a  discrepancy  between  the 
calendar  and  the  moon  was  purposely  created.  The  calendar  of  the  Metonic 
cycle  is  independent  of  any  such  arrangement  of  the  ecclesiastical  calendar. 


HISTOEICAL  CHKONOLOGY  49 

in  the  Metonic  cycle  they  stood  as  they  had  been 
arranged  to  suit  the  era  of  Christ.  And  the  point 
is  that,  as  that  era  commenced  three  years  before  the 
era  Dionysius  was  substituting  for  it,  he  would  of 
necessity,  on  deciding  to  change  the  golden  numbers, 
have  made  his  number  I  take  the  place  of  number  IV 
of  the  era  of  Christ,  if  the  calendar  moon  then  agreed 
with  the  real  moon  and  if  he  wished  it  to  continue  to 
do  so.  If  he  had  made  that  change,  he  would  simply 
have  reverted  to  the  original  numbering  of  the  Metonic 
cycle. ^  But,  instead  of  moving  his  numbers  three  years 
forward,  he  moved  them  three  years  hack,  making  his 
number  I  take  the  place  of  number  XVII ;  -  so  that  the 
golden  numbers  of  the  existing  era  must  be  considered 
to  commence  either  three  years  before  or  else  sixteen 
years  after  those  of  the  era  of  Christ,  though  the  era 
itself  undoubtedly  began  three  years  after  the  era  of 
Christ.  That  seems  to  confirm  the  view  I  have  already 
expressed  to  the  effect  that  he  selected  for  the  golden 
number  of  his  epoch  year  the  March  new  moon  of  the 
calendar,  which  best  suited  as  a  starting  point  for  the 
era  ;  and  it  makes  him  appear  to  have  cared  as  little 
for  the  relative  positions  of  the  new  and  the  old  golden 
numbers  as  for  the  relative  phases  of  the  real  moon 
and  those  of  the  moon  of  the  calendar. 

A  third  peculiarity  which  I  have  not  seen  alluded  to, 
and  which  seems  worthy  of  special  attention  as  throwing 

'  That  which  (as  shown  in  Table  II.)  Bond  treats  as  the  original  cycle, 
but  which  appears  to  me  to  have  been  framed  more  recently. 

-  Supposing  the  relative  positions  of  the  numbers  in  Bond's  table  to 
be  correct ;  but  I  have  (in  connection  with  Table  V.)  shown  that  Meton's 
number  XVII,  to  which  number  I  of  the  era  of  Christ  was  applied,  is 
that  now  in  use. 

D 


50  ASTRONOMICAL  AND 

a  new  light  through  the  confusion,  is  that  Bond  gives 
July  13,  432  B.C.  as  the  epoch  of  Meton's  cycle  without 
specifying  any  authority  for  that  date  (which  has  in 
fact  become  generally  accepted) ;  whereas  Playfair  gives 
July  16,  433  B.C.  and  states  that  a  new  moon  which 
occurred  at  7.43  p.m.  on  that  day  fixed  Meton's 
epoch. 

The  point  is  that,  if  Playfair  is  right  as  regards  the 
day  of  the  month,  then  the  new  moons  of  golden 
number  I  in  Meton's  original  calendar  have  been  made 
to  correspond  with  golden  number  I  of  the  cycle  which 
Bond  gives  as  that  of  the  Saxon  Charters,  but  the 
golden  numbers  themselves  as  we  now  use  them  stand 
just  as  originally  arranged  by  Meton,  forming  the  only 
unbroken  record  of  years  which  has  existed  from  so 
early  a  date  in  Europe ;  and  his  cycle  must  have  com- 
menced in  437  B.C.  (astronomical = vulgar  438  B.C.), 
which  is  23  cycles  before  the  year  0  (vulgar  1  B.C.). 

The  evidence  in  support  of  the  above  view  is  as 
follows  : 

According  to  both  Playfair  and  Bond,  the  123rd  of  the 
Metonic  cycles  is  now  current  and  not  far  from  ended  ; 
and  in  that  time  the  moon  must  have  advanced  in  rela- 
tion to  the  calendar  moon  rather  more  than  10^  days 
(122x2"  5™  =  10''  14"  10"^  and  123x2"  5"^=10'^  16" 
15"). 

That  makes  Playfair' s  new  moon  of  July  16  corre- 
spond with  the  new  moon  of  July  26,  1881,  as  ending 
the  122nd  cycle,  and  the  new  moon  of  July  26,  1900, 
as  ending  the  123rd  cj^cle.  And,  as  123  cycles  are 
2337  years,  Playfair's  new  moon  of  July  16  must 
have   been   July  16,   437  B.C.  astronomical,  which  is 


HISTOEICAL  CHRONOLOGY  ol 

438  B.C.  of  vulgar  reckoning  (not  433,  as  recorded  by 
him).i 

'  An  exact  verification  of  the  advance  of  the  moon  from  the  almanac 
dates  of  Meton's  time  cannot  be  made  without  having  the  liour,  as  well 
as  the  day,  of  each  new  moon  of  his  calendar.  For  an  approximation, 
the  days  of  new  moons  in  his  calendar  must  be  set  against  the  days  of 
the  corresponding  moons  in  our  almanac,  disregarding  the  additional 
hours  of  each  moon.  Tested  in  that  manner,  the  average  advance  of 
the  dates  of  the  moons  in  our  almanac  from  the  corresponding  dates  of 
the  calendar  in  Table  III.  is  9  days  20  hours,  instead  of  10  days  16  hours, 
making  an  apparent  discrepancy  of  20  hours.  The  greater  part  of  that 
discrepancy  is,  however,  accounted  for  by  13^  hours  included  in  the 
2  days  14  hours  24  minutes  which  the  calendar  gains  in  10,000  years, 
as  explained  on  page  33  (10,000  years  :  2  days  14  hours  24  minutes 
::  2,337  years  :  13|  hours).  And  that  the  remaining  difference  (6|  hours) 
is  due  to  the  allowance  of  leap  years  having  given  a  correction  in  excess 
of  what  had  been  immediately  requisite  when  the  last  February  29  had 
been  inserted,  is  shown  by  the  fact  that  the  omission  of  February  29  in 
the  year  1900  has  made  the  average  amount  by  which  the  moons  from 
July  1900  to  December  1904  are  in  advance  of  Meton's  calendar  10  days 
21  hours,  thus  approximately  reversing  the  discrepancy. 

Another  test  is  obtained  by  deducting  Meton's  epoch  from  the  conclu- 
sion of  his  123rd  cycle,  as  follows  : 

437  B.C.  July  16 
from  1900  a.d.  July  26 

difference  2337  years 

2h.  5m.  X  123  cycles  = 

difference  0     22     15 

By  making  the  year  1900  a  leap  year,  the  date  of  the  above  new  moon 
would  have  been  July  25,  Ih.  43m.  p.m.,  making  the  difference  Id.  22h. 
15m. ;  so  that  the  omission  of  February  29  in  the  year  1900  appears  by 
this  test  also  to  leave  more  than  half  a  day  accumulated  towards  another 
omission  not  yet  fixed  in  the  almanac. 

As  a  basis  for  the  discussion  of  this  subject  it  is  necessary  to  recognise 
that  though,  by  a  discrepancy  in  one  direction  chancing  to  counterbalance 
another  discrepancy  due  to  some  other  cause,  the  almanac  might  possibly 
coincide  with  the  moon  at  different  dates,  and  show  the  same  period  for 
separate  lunations,  the  existence  of  secular  acceleration  makes  it  impos- 
sible for  such  a  coincidence  to  be  effected  by  a  recurrence  of  the  same 
causes  in  any  cycle. 


7h 

.  43m. 

1 

43 

9 

18 

0 

10 

16 

15 

62  ASTHONOMICAL  AND 

As  William  Smith,  after  saying  that  '  the  acknow- 
ledged epoch  of  commencement  of  the  period  has  been 
placed  B.C.  482,'  further  says,  '  but  we  are  far  from 
seeing  how  it  has  been  made  out,' '  it  seems  to  me  that 
the  argument  I  have  given  probably  establishes  the 
true  epoch. 

That  makes  it  appear  that  Dionysius  must  have 
found  Meton's  original  cycle  with  the  calendar  moons 
readjusted  to  an  early  period  of  the  Christian  era,  and 
brought  it  back  into  use  as  he  found  it ;  and  also  that 
the  cycle  which  Bond  gives  as  Meton's  must  have  been 
framed  for  some  subsequent  purpose. 

It  is  easy  to  be  misled  in  the  confusion  which  has 
been  created  in  connection  with  the  calendar ;  but  it 
appears   nevertheless   not  out  of  place,  in  connection 

If  there  were  stability  of  action  in  the  forces  by  which  the  solar 
system  is  controlled,  then  (except  slight  differences  in  the  effects  of  per- 
turbations by  the  planets)  there  would  be  equal  intervals  of  time  between 
each  recurrence  of  a  new  moon  at  (1)  the  same  distance  from  the  earth, 
(2)  the  same  distance  from  the  sun,  (8)  the  same  distance  from  the  plane 
of  the  earth's  equator,  (4)  the  same  distance  from  the  plane  of  the  sun's 
equator,  and  (5)  with  the  earth  in  the  same  position  in  relation  to  the 
sun  and  moon  ;  but  a  changing  ratio  of  forces  prevents  a  recurrence  of 
all  those  conditions  in  combination,  as  certainly  as  the  course  of  evolu- 
tion prevents  any  man  from  being  twenty-one  years  old  twice  in  his 
life.  A  verification,  subject  to  a  small  discrepancy  which  would  represent 
the  secular  acceleration  combined  with  a  slight  difference  in  planetary 
action  in  each  cycle,  which  latter  is  on  the  average  a  retarding  action, 
but  greater  in  some  cycles  than  in  others,  could  be  arrived  at  by  calculating 
the  position  of  Meton's  epoch  new  moon  in  all  the  five  above  specified 
respects,  to  make  the  requisite  allowance  for  divergence  of  the  new  moon 
of  July  26, 1900,  from  each  position.  That  elaborate  analysis  is  not,  how- 
ever, I  think,  required  for  my  purpose,  as  the  rough  approximations 
I  have  given  appear  sufiicient  to  establish  my  argument. 

'  Dictionary  of  Greek  and  Eonian  Biography,  edited  by  William 
{Smith,  vol.  ii.  p.  1009.     (John  Murray,  1840.) 


HISTOEICAL  CHRONOLOGY  53 


( 


with  my  argument,  to  give  the  foregoing  indication  re- 
garding Meton's  epoch  quantum  valeat. 

If  the  cycle  of  golden  numbers  now  in  use  really  is, 
as  I  have  suggested,  Meton's  original  cycle,  the  question 
arises  as  to  w^hat  is  the  origin  of  that  v^hich  Bond  has 
considered  to  be  Meton's  original  cycle.  That  cycle 
seems  to  me  to  have  been  framed  after  the  commence- 
ment of  our  era  with  the  year  of  the  Crucifixion  for  its 
epoch. 

The  evidence  bearing  on  that  point  is  the  fact  that 
in  the  year  1896  the  moon  had  gained  eight  days 
on  the  calendar  which  Bond  treats  as  being  the  one 
originally  created  by  Meton  in  432  B.C. ;  and,  therefore, 
instead  of  corresponding  with  the  calendar  in  Meton's 
time,  it  conformed  with  it  at  or  after,  rather  than 
before,  the  Christian  epoch  ;  so  that  it  is  probably  a 
reorganisation  of  Meton's  calendar  created  for  some  era 
brought  into  use  about  that  date.  And  as  the  golden 
number  I  of  that  calendar  corresponds  with  33  A.D., 
which  is  the  generally  accepted  date  of  the  Crucifixion, 
the  two  coincidences  justify  its  being  regarded  as  the 
cycle  which  was  used  with  the  *  Era  of  the  Crucifixion  ' 
in  the  absence  of  definite  evidence  to  the  contrary.^     All 

'  Taking  the  full  moon  which  occurred  between  the  new  moons  of 
March  6  and  April  5,  33  A.D.,as  the  epoch  of  the  era,  the  average  advance 
of  the  moons  of  the  first  five  years  of  the  calendar  given  in  Table  IV.  is 
8  days  6  hours  ;  which,  with  12  hours  accumulated  towards  the  correction 
of  tlie  almanac  independently  of  the  organised  leap  years  (as  explained 
on  page  33),  makes  the  average  advance  shown  by  those  five  years  8  days 
18  hours ;  which  shows  the  calendar  to  have  been  correctly  adjusted  to 
the  moon  in  33  a.d.  The  evidence  is  to  the  effect  that  golden  number  I 
was  applied  to  the  calendar  moons  of  March  6  and  April  5,  because 
those  were  the  dates  of  the  real  new  moons  at  the  time  of  the  Crucifixion ; 
and  subsequent  arrangements  have  chanced  to  make  33  a.d.  correspond 
with  them. 


54  ASTRONOMICAL   AND 

tlmt  concerns  my  argument,  liowever,  is  that  it  certainly 
is  not  Meton's  original  cycle.  The  evidence  based  on 
that  calendar  is  that  the  full  moon  of  the  Crucifixion 
occurred  between  real  new  moons  of  March  6  and 
April  5  ;  and  also  that  golden  number  I  was  therefore 
applied  to  those  moons,  and  was,  together  with  them, 
given  the  position  properly  belonging  to  Meton's  golden 
number  XV,  which  is  the  number  belonging  to  33  a.d. 
in  both  those  months.  The  moons  of  Meton's 
number  XV  are  March  5  and  April  4,  and  had 
advanced  a  full  day  when  the  Era  of  the  Crucifixion 
w^as  framed.^  Table  IV.  serves  to  elucidate  that  point. 
The  invalidation  of  the  claim  of  that  cycle  to  be 
considered  Meton's  is  a  further  argument  for  con- 
sideration of  that  which  I  have  given  in  Table  III. 

It  appears  to  be  mere  matter  of  fact  (be  the  ex- 
planation what  it  may)  that  the  calendar  moons  of  the 
cycle  now  in  use  were  moved  to  their  present  positions 
4  golden  numbers  in  advance  of  those  against  which 

'  In  Table  IV.  I  have  altered  the  relative  positions  given  by  Bond  to 
the  golden  numbers  of  the  two  cycles,  but  in  doing  so  I  keep  in  accord 
with  an  argument  alluded  to  by  him  to  the  effect  that  the  Crucifixion 
occurred  in  a  year  of  Meton's  cycle  number  XV  (see  p.  233  of  his  1875 
edition),  together  with  my  argument  to  the  effect  that  he  has  mistaken 
the  golden  numbers  of  the  Era  of  the  Crucifixion  (instead  of  our  present 
numbers)  for  Meton's  original  numbers. 

It  therefore  appears  that  the  generally  accepted  date  of  the  Cruci- 
fixion, and  my  argument  regarding  the  relation  of  those  calendars, 
mutually  confirm  each  other;  whereas  Bond's  argument  leads  him  to 
make  the  date  of  the  Crucifixion  30  a.d.  ;  and  his  divergence  from  the 
accepted  opinion  seems  to  be  explained  by  the  facts  that  his  arguments 
are  based  to  some  extent  on  what  he  supposes  to  be  Meton's  cycle,  but 
which  he  treats  as  commencing  its  golden  number  I  in  what  is  really 
Meton's  number  IV ;  so  that  the  true  date  is  three  years  in  advance  of 
that  supposed  by  Bond, 


HISTORICAL  CHRONOLOGY  65 

they  stood  in  the  calendar  used  with  the  era  of  Christ, 
and  that  the  change  brought  them  approximately  into 
accordance  with  the  real  moon,  not  at  the  time  of  the 
Dionysian  Keformation,  nor  at  the  epoch  of  the  Christian 
era,  but  at  that  of  the  era  of  Diocletian,  284  a.d.  ;  so 
that  as  Dionysius,  while  discarding  the  era  of  Christ, 
discarded  also  the  calendar  framed  for  that  era,  he  may 
probably,  while  also  discarding  the  era  of  martjTS, 
have  either  kept  in  use,  or  else  brought  back  into  use, 
the  calendar  which  had  been  specially  framed  for  that 
era;  for  the  era  of  martyrs  was  merely  the  name 
applied  by  Christians  to  the  era  of  Diocletian,  which 
was  for  a  long  time  the  prevalent  and  official  era  in 
Eome.^ 

And  it  also  appears  to  be  mere  matter  of  fact  that 
the   calendar   used   with   the   era    of    Christ,    which 

'  The  era  of  martyrs  is  referred  to  by  some  writers  as  if  it  were  a 
Christian  era  estabHshed  to  commemorate  the  multitude  who  were 
cruelly  slaughtered  in  the  reign  of  Diocletian,  and  Bond  says  nothing  in 
definite  refutation  of  that  erroneous  idea.  In  his  Preface  he  says  '  the 
early  Christians  adopted  an  era  which  they  called  the  Era  of  Martyrs.' 
And  when  stating  that  the  era  is  '  also  called  the  Era  of  Diocletian,'  he 
says  it  dates  from  the  reign  of  Diocletian  '  in  consequence  of  the  persecu- 
tions of  the  Christians  by  that  emperor.'  The  fact  is  that  the  era  was 
not  in  any  sense  a  consequence  of  those  persecutions ;  and  when  it  was 
established  in  284  a.d.  Diocletian  was  quite  the  reverse  of  a  persecutor. 
The  cruelties  which  led  the  early  Christians  to  abhor  the  use  of  his 
name  occurred  in  303  a.d.,  and  are  considered  by  Gibbon  to  have  been 
the  cause  of  Diocletian's  abdication.  The  action  of  Pope  Hilarius  in 
substituting  the  era  of  Christ  for  the  era  of  martyrs  seems  to  have  been 
influenced  by  the  same  feeling  as  that  which  had  led  Christians  to  sub- 
stitute the  term  Era  of  Martyrs  for  Era  of  Diocletian. 

In  establishing  an  era  dating  from  his  own  reign,  Diocletian  followed 
the  example  set  by  Caesar ;  but  if  Casar  had  been  satisfied  with  reform- 
ing the  era  of  Eome  without  introducing  a  new  era,  it  seems  unlikely 
that  any  emperor  could  have  ventured  to  displace  it,  and  the  reason 
which  led  the  Christian  world  to  do  so  would  not  have  existed. 


56  ASTRONOMICAL   AND 

Dionysius  discarded,  is  Meton's  original  calendar 
moved  bodily — that  is  to  say,  the  golden  numbers 
moved  together  v^ith  their  corresponding  moons — three 
years  back  from  their  original  position  in  time  ;  that 
is  to  say,  from  the  positions  in  which  the  calendar 
moons  and  the  respective  golden  numbers  would  have 
stood  if  Meton's  calendar  had  been  undisturbed.  That 
is  made  clear  by  comparison  of  Tables  III  and  V.^ 

The  cycle  of  golden  numbers  which  Bond  gives  as 
those  used  in  Saxon  Charters,  and  as  having  been  intro- 
duced in  463  A.D.,  must  therefore,  if  that  is  the  true 
date  of  its  origin,  have  been  expressly  arranged  by 
Pope  Hilarius  to  suit  the  era  of  Christ ;  and  his  re- 
organisation consisted  merely  of  a  change  in  the 
position  of  Meton's  calendar  by  pushing   it   back  so 

•  The  golden  numbers  may  have  been  continued  to  be  applied  to  all 
the  same  calendar  moons  as  in  Meton's  calendar ;  but  I  have  made 
number  I  in  Table  V.  begin  with  the  December  new  moon  preceding  the 
lull  moon  of  the  first  Christmas  Day,  because  the  coincidence  of  Meton's 
original  number  I  with  the  full  moon  of  the  first  Christmas  Day  is  all 
that  concerns  my  argument.  The  new  moon  of  December  23,  1897, 
completed  100  cycles  from  the  epoch  of  the  era  of  Christ,  showing  an 
advance  of  13  days  on  the  calendar  moon  of  December  10 ;  which  makes 
it  evident  that  there  was  never  any  pretence  of  adjusting  the  moons 
of  that  calendar  with  the  real  moon.  That  calendar  accords  with  the 
moon  nearly  1,000  years  before  Meton's  time. 

I  take  it  for  granted  that  Bond  has  given  correctly  the  calendar  moons 
for  the  respective  cycles  ;  and  the  evidence  I  have  adduced  seems  to  me 
to  justify  the  change  I  have  made  in  the  relative  positions  of  the  golden 
numbers  themselves.  I  have  (on  page  48)  commented  on  the  peculiarity 
of  the  relative  positions  of  the  numbers  in  Bond's  table ;  and  the 
admitted  fact  that  the  era  of  Christ  began  three  years  before  our  era  fixes 
its  epoch  to  our  golden  number  XVII,  so  that  if  golden  number  I  was 
applied  to  the  epoch  of  the  era  of  Christ-it  must  of  necessity  correspond 
with  our  number  XVII,  And,  also,  as  Bond  makes  the  era  of  Christ 
begin  with  what  he  calls  Meton^s  number  XVII,  the  question  is  as  to 
which  of  the  two  cycles  really  is  Meton's. 


HISTORICAL  CHRONOLOGY  67 

as  to  make  the  full  moon  which  occurs  on  Christmas 
Day  in  his  calendar  coincide  with  December  25,  750 
A.U.C.,  which  he  had  fixed  on  as  the  epoch  for  the  com- 
mencement of  the  era  of  Christ,  though  the  change  did 
not  bring  the  calendar  moon  into  conformity  with  the 
real  moon.  That  calendar  must  have  been  created  in 
that  manner  whether  it  originated  at  the  time  of  Pope 
Hilarius  or  at  any  other  time.  Neither  Playfair  nor 
the  author  of  '  L'Art  de  Verifier  les  Dates  '  appears  to 
have  had  knowledge  of  the  calendar  of  the  era  of 
Christ ;  but  it  seems  probable  that  evidence  may  be 
found  of  it  having  been  used  in  many  parts  of  Europe 
before  the  era  of  the  Incarnation  was  invented  by 
Dionysius.  If  it  is  the  calendar  used  in  Saxon 
Charters  in  England,  it  must  have  been  brought  into 
this  country  before  the  time  of  St.  Augustine,  as  he 
would  not  have  introduced  it  after  the  Christian  era 
organised  by  Dionysius  had  been  adopted  in  Kome. 
In  the  printed  list  of  old  documents  in  the  British 
Museum  there  is  not,  however,  anything  in  confirma- 
tion of  this  suggestion. 

There  probably  exist  in  some  old  libraries  records 
regarding  the  relative  ages  of  these  calendars.  The 
evidence  I  find  available  is  to  the  effect  that  the  calendar 
which  Bond  gives  as  Meton's  was  in  fact  created  after 
the  epoch  of  the  Christian  era.  That  evidence  is 
given  by  the  position  of  the  moon  of  that  calendar  in 
relation  to  the  real  moon,  and  by  the  coincidence  of 
its  golden  number  I  with  the  accepted  date  of  the 
Crucifixion.  And  the  evidence  as  regards  the  calendar 
used  with  the  era  of  Christ  is  that  it  was  created  by 
Pope  Hilarius  to  be  used  in  substitution  of  that  specially 


58  ASTRONOMICAL   AND 

created  for  the  era  of  Diocletian  ;  ]mt  the  calenclar 
itself  gives  no  clue  as  to  the  date  of  its  creation.  Its 
golden  number  I  is,  however,  so  displaced  from  its 
position  in  Meton's  calendar  as  to  show  that,  what- 
ever may  have  been  the  date  of  its  origin,  it  was 
created  specially  for  the  era  of  the  Nativity.  Whatever 
may  have  been  the  case  as  regards  the  calendar  of  the 
era  of  the  Crucifixion,  it  is  evident  that  the  calendar  of 
the  era  of  Christ  must  at  one  time  have  been  used  in 
Rome  in  substitution  of  that  of  the  era  of  Diocletian  ; 
and,  in  the  absence  of  evidence  of  the  latter  having  been 
reverted  to  before  the  time  of  Dionysius,  it  appears 
that  he  discarded  not  only  the  era  of  Christ,  but  also 
the  calendar  which  had  been  framed  for  it,  and  re- 
adopted  the  calendar  of  Diocletian  for  use  with  the 
vulgar  Christian  era.  It  is  quite  possible,  or  indeed 
most  probable,  that  Dionysius  and  those  acting  with 
him  were  influenced  by  the  fact  that  the  course  they 
were  taking  replaced  Meton's  golden  numbers  in  their 
true  positions,  making  them  a  correct  record  of  years 
from  Meton's  epoch ;  at  any  rate,  it  appears  that  they 
effected  that  useful  reform,  whether  by  deliberation  or 
accident. 

If  Dionysius  did  not  knowingly  revert  to  Meton's 
cycle  when  discarding  that  of  the  era  of  Christ,  as  I 
have  suggested,  the  alternative  explanation  is  that  the 
calendar  of  Diocletian,  which  must  have  been  then 
well  known,  had  been  framed  on  Meton's  original 
cycle  with  the  calendar  moons  adjusted  to  the  true 
moon  at  the  Diocletian  epoch  without  disturbing  the 
golden  numbers,  and  as  Dionysius  did  not  adjust  the 
calendar   to   the   moon   in    532   a.d.,   the   probability 


HISTORICAL  CHRONOLOGY  59 

seems  to  be  that  he  merely  re-adopted  the  use  of  the 
calendar  of  Diocletian  as  it  stood. 

De  Morgan  says  :  '  Dionysius  Exiguus  seems  to  have 
done  no  more  than  accommodate  the  cycle  of  Vic- 
torinus  to  his  new  mode  of  reckoning ;  he  being  the 
person  who  first  abandoned  the  era  of  Diocletian,  and 
reckoned  from  the  supposed  year  of  the  birth  of 
Christ;  ' 

As  *  the  cycle  of  Victorinus  '  is  that  of  Pope  Hilarius, 
De  Morgan's  statement  confirms  the  view  I  have  given 
as  to  the  era  of  Christ  having  been  substituted  in 
Kome  for  that  of  Diocletian ;  but  the  tables  I  have 
appended  and  the  arguments  referred  to  in  them  show 
that,  if  that  was  so,  Dionysius  deliberately  abandoned 
the  cycle  and  calendar  moons  framed  for  the  era  of 
Christ  together  with  the  era. 

The  acceptance  of  the  argument  to  the  effect  that 
the  golden  numbers  as  now  used  stand  as  placed  in 
Meton's  original  cycle  vitiates  arguments  Bond  has 
based  on  the  supposition  of  Meton's  cycle  having  been 
that  which  appears  to  me  to  have  been  created  for  the 
era  of  the  Crucifixion  ;  ^  but  I  cannot  point  that  out 
without  expressing  an  opinion  to  the  effect  that  Bond's 
work  is  the  most  valuable  contribution  to  chronology 
since  the  publication  of  '  L'Art  de  Verifier  les  Dates.' 

'  Article,  '  On  the  Ecclesiastical  Calendar,'  p.  9,  by  A.  De  Morgan, 
The  British  Almanac,  1845. 

-  Bond  does  not  state  his  authority  for  what  he  supposes  to  be 
Meton's  cycle.  But  he  seems  to  have  accepted  its  identity  as  an 
established  fact,  and  to  have  based  arguments  confidently  upon  it  without 
any  thought  of  questioning  the  historical  accuracy  of  that  supposed 
origin.  It  seems  to  me  that  he  is  certainly  mistaken  where  (on  page  xxxii 
of  his  Preface)  he  supposes  it  to  be  the  one  which  was  in  use  by  the  Jews 
in  the  time  of  Christ. 


60  ASTRONOMICAL    AND 

De   Morgan's   interesting   contributions '    do  not  pre- 
tend to  a  position  of   such   practical  utility ;   and  he 
appears  to  have  misappreciated  the  importance   of  a 
correct  record  of  time,  as  he  alludes  to  the  Gregorian 
Eeformation  as  '  the    stupid  expedient  of    destroying 
ten    nominal    days,    which    has    created    more    con- 
fusion  and    more    chronological    error    than    all   the 
anomalies  of  the  old  calendars  put  together.     .     .     . 
The  Gregorian  Eeformation  has  done  much  in  this  way ; 
another  attempt  would  go  near  to  render  the  chronology 
of  the  country  in  which  it  was  made  an  unfathomable 
mystery.'  ^     Most  practical  men   will,  I   think,  agree 
that   the  mischief  was  created   by   those   w^ho  failed 
throughout  the  '  Dark  Ages '  to  act  on  the  principles 
on  which  the  Julian  Eeformation  had  been  based,  and 
that  the  Gregorian  Eeformation  merely  grappled  with 
that  mischief  and  prevented  the  years  from  ceasing  more 
and   more  to  constitute  a  true  record  of   time.     The 
plea  oi  factum  valet  superimposed  vo^on  fieri  non  dehuit 
is  too  often  urged  against  the  revision  of  such  mis- 
takes as  that  for  which  the   Gregorian  Eeformation 
contrived  a   practical  correction  ;    and   any  confusion 
now   connected  with  it  may  be    considered  as    of   a 
trifling  character  in  comparison  with  that  of  the  con- 
fusion which  it  averted. 

A  more  practical  view  of  the  question  is  expressed 
by  Sir  Harris  Nicolas,  who  says  :  '  The  absurdity  of 
retaining  the  25th  of  March  as  the  beginning  of  the  year, 
not  because  it  was  the  25th  of  March,  but  because  it 
was   the  time  of  the  vernal  equinox,   which,  in  the 

'  Tlie  British  Almanac,  1845,  1840. 

-  Ihid.  '  On  the  Ecclesiastical  Calendar,'  pp.  12-36. 


HISTORICAL  CHRONOLOGY       •  61 

eighteenth  century,  had  receded  so  far  back  as  from 
the  25th  to  about  the  10th  of  March,  was  forcibly 
urged  by  Wilson  in  1735.  .  .  .  These  anomalies, 
nevertheless,  continued  for  seventeen  years  longer ;  and 
the  reformation  of  the  calendar,  when  it  did  take  place, 
was  offensive  in  the  highest  degree  to  a  large  part  of 
the  kingdom.'  ^ 

De  Morgan  alludes  to  the  illness  and  death  of  the 
Astronomer  Royal,  James  Bradley,  having  been  '  attri- 
buted to  a  judgment  from  Heaven,'  as  if  he  intended 
the  animosity  aroused  against  Bradley  to  serve  as  a 
warning  to  all  men  in  positions  of  authority  to  leave 
established  errors  uncorrected ;  -  but,  I  think,  most  men 
will  now  consider  Bradley's  action  in  the  matter  to 
have  been  more  worthy  of  his  position  in  the  scientific 
world  than  De  Morgan's  policy  of  inaction. 

The  confusion  has  been  a  necessary  consequence  of 
applying  Meton's  cycle  to  a  purpose  for  which  it  is 
not  suitable.  To  get  a  really  perpetual  calendar  the 
ecclesiastical  authorities  ought  to  have  used  thirty 
'  golden  numbers  '  instead  of  nineteen ;  making  the 
number  of  the  first  day  on  which  a  new  moon  occurred 
in  any  year  the  golden  number  for  that  year. 

Under  such  an  arrangement  the  moon  could  never 
escape  more  than  a  fraction  of  a  day  from  the  calendar 
moon,  and  the  latter  would  automatically  readjust  itself 
to  the  moon  instead  of  allowing  the  discrepancy  to 
accumulate  as  it  does  in  Meton's  cycle. 

The   above   arrangement   would   not   have    suited 

'  The  Chronology  of  History,  by  8ir  Harris  Nicolas,  K.C.M.G.,  183.3 
(London  :  Longman,  Kees,  Orme,  Brown,  Green,  &  Longman). 
-  '  On  the  Ecclesiastical  Calendar,'  p.  131. 


62  ASTBONOMICAL   AND 

Meton,  because  he  required  numbers  to  use  in  arith- 
metical sequence ;  but  it  appears  to  me  that  for  the 
purposes  of  the  calendar  the  sequence  of  the  golden 
numbers  is  as  immaterial  as  that  of  the  Dominical 
Letters. 

Si  quid  novisti  rectius  istis, 
Candidus  imperti ;  si  non,  his  uteie  mecum. 

As  the  Koman  era  prevailed  in  Europe  at  the  time 
of  the  introduction  of  our  present  era,  it  is  of  interest 
to  record  that  it  is  now  certain  that  the  year  1  of 
Kome  does  not  correctly  represent  the  year  of  the 
foundation  of  that  city,  regarding  which  there  are  wide 
discrepancies  of  opinion,  whereas  as  regards  the  year 
1  of  Nabonassar  the  only  doubt  is  as  to  whether  it 
represents  the  year  of  the  foundation  of  the  Second 
Babylonian  Empire  or  the  second  year  of  that  empire. 
It  is  a  point  of  interest,  because  the  year  of  Eome, 
framed  by  Julius  Caesar,  and  the  year  of  Nabonassar, 
framed  by  that  king  at  the  commencement  of  the 
Second  Babylonian  Empire,  are  the  two  antecedent 
phases  through  which  our  present  system  has  been 
evolved  from  a  chaos  of  lunar,  luni-solar,  and  solar 
measures  of  time,  which  appears  to  have  been  some- 
times made  to  run  fast  by  counting  lunations  as 
years. 

The  solar  year  seems  to  have  been  undoubtedly 
invented  in  Egypt,  whether  by  Edomite  invaders, 
Jewish  conquerors  of  the  latter,  or  by  native  Egyptians. 
It  was  never  officially  adopted  by  the  Jews,  but  became 
important  in  chronology  through  its  adoption  by 
Nabonassar  in  Babylon  in  displacement  of  the  year 
of  twelve  lunations,  with  occasional  intercalary  months 


HISTOEICAL  CIIEONOLOGY  63 

as  still  used  by  the  Chinese  ;  and  it  became  firmly 
established  in  Europe  by  the  Julian  and  Gregorian 
Reformations.  It  is  well  to  recognise  that  the  Gre- 
gorian Reformation  was  necessitated  only  because  up 
to  the  time  of  Gregory  XIII.  the  successors  of  Julius 
Caesar  failed  to  act  on  the  principles  on  which  the 
Julian  Reformation  was  based. 

The  immediate  origin  of  the  solar  year  as  the  unit 
of  measure  in  the  scale  of  time  is  narrated  by  Sir 
Isaac  Newton,  who  says  ^  that  King  David's  conquest 
of  the  Edomites  gave  him  possession  of  ports  on  the 
Red  Sea,  and  at  the  same  time  the  Edomites,  driven  by 
him  into  Egypt,  became  the  first  inventors  of  the  use  of 
sailing  ships  by  availing  of  the  art  of  making  linen  cloth 
already  known  in  Egypt,  and  thus  created  an  extension 
of  commercial  enterprise  which  '  gave  a  beginning  to 
astronomy  and  navigation.'  The  navigators  were 
obliged  to  observe  the  positions  of  the  stars  to  enable 
them  to  know  their  course  when  out  of  sight  of  land, 
and  were  thus  led  to  the  invention  of  the  solar  year  of 
365  days,  which,  300  years  after  David's  extension  of  his 
kingdom  to  the  Red  Sea,  was  adopted  in  Babylon  as  the 
year  of  Nabonassar.  The  merits  of  that  system  were 
doubtless  well  known  in  Jerusalem  long  before  they 
became  known  in  Babylon,  though  the  vast  importance 
attached  to  ritual  in  the  religious  ceremonies  of  the 
Jews  made  the  official  recognition  of  the  system  in  use 
among  the  Jewish  traders  impossible  in  their  own 
country.  The  rapid  development  of  trade  and  com- 
merce which  followed  the  appearance  of  the  Jews  on 
the  Red  Sea  as  a  powerful  nation  rendered  the  reign  of 

'  Horsley's  edition  of  Newton's  Woiks,  vol.  v.  pp.  13-5  &c. 


64  ASTRONOMICAL  AND 

King  Solomon  one  of  the  most  important  epochs  in 
the  world's  history  ;  and  the  astronomy  of  Egypt  was 
carried  to  Babylon  by  the  extension  of  ocean  commerce 
inaugurated  by  the  Jews  through  the  Bed  Sea  and  the 
Persian  Gulf.  The  extension  of  trade  and  commerce 
which  was  inaugurated  by  King  David  may  well  be 
regarded  as  of  not  less  epoch-making  importance  in 
the  history  of  the  world  than  that  which  followed  the 
discovery  of  the  western  hemisphere  in  the  reign  of 
Ferdinand  and  Isabella. 

In  his  chapter  on  the  'Chronology  of  the  Greeks,' 
Sir  Isaac  Newton  makes  some  remarks  which  may  well 
be  recapitulated  for  the  purpose  of  eliminating  sectarian 
spirit  from  the  merits  of  the  question  as  to  the 
improvement  of  the  existing  system  of  chronology. 

Newton  concludes  that  chapter  by  saying  that 
'  the  morality  and  religion  of  the  first  ages  still  called 
by  the  Jews  *' The  precepts  of  the  sons  of  Noah"  is 
the  primitive  religion  of  both  Jews  and  Christians,  and 
ought  to  be  the  standing  religion  of  all  nations,  it 
being  for  the  honour  of  God  and  good  of  mankind. 
....  The  believing  that  the  world  was  framed  by  one 
supreme  God,  and  is  governed  by  him  ;  and  the  loving 
and  worshipping  him,  and  honouring  our  parents,  and 
loving  our  neighbour  as  ourselves  ;  and  being  merciful 
even  to  brute  beasts,  is  the  oldest  of  all  religions.' 

Those  words  of  Sir  Isaac  Newton  seem  appropriate 
and  worthy  of  consideration  in  connection  with  any 
attempt  to  strengthen  the  foundations  of  the  Christian 
era. 

What  is,  however,  immediately  practical  in  the 
subject   is   the   fact  that  there  has  never  existed  any 


HISTORICAL   CHEONOLOGY  65 

system  of  chronology  which,  whether  considered  on 
its  theoretical  merits  or  as  regards  its  extensive  practical 
use  in  scientific  records,  can  be  placed  in  rivalry  with 
the  present  astronomical  system  ;  and  the  arguments 
I  have  adduced  show,  I  think,  its  point  of  variance  as 
regards  our  vulgar  system  to  be  due  to  an  error  in  the 
latter  which  admits  of  easy  reformation  so  as  to 
identify  vulgar  with  astronomical  reckoning. 

The  most  important  reform  ever  effected  in 
chronology  is  that  by  which  the  practical  system 
invented  by  the  necessities  of  commerce  was  officially 
substituted  in  the  Babylonian  Empire  for  what  had 
previously  been  their  vulgar  system ;  and  a  further 
development  is  now  called  for  to  bring  the  system 
practically  forced  on  astronomical  science  officially  into 
our  vulgar  chronology. 

Many  eras  have  been  used  for  chronological  records, 
and  until  one  has  been  established  on  a  correct  basis 
rival  eras  will  doubtless  continue  to  compete  in  the 
struggle,  in  which  the  fittest  will  survive. 

The  tangled  confusion  of  records,  even  since  the 
establishment  of  the  Christian  era,  leads  Mr.  Arbuthnot, 
to  whose  work  I  have  above  referred,  to  propose  that 
we  should  inaugurate  a  new  era  dating  from  the  com- 
mencement of  the  reign  of  Queen  Victoria ;  but  such 
a  course  would,  like  the  similar  action  of  the  first 
French  Eepublic,  make  confusion  worse  confounded 
\\dthout  any  compensating  advantage  to  be  gained  by 
attempting,  like  the  first  French  republicans,  to  displace 
an  era  which  has  become  accepted  wherever  European 
civilisation  has  established  itself.  The  more  natural 
and  expedient  course  appears  rather  to  be  to  disentangle 

E 


66  ASTRONOMICAL  AND 

as   far   as  possible  those   records   and   establish   their 
true  positions  in  the  existing  era. 

In  '  Macmillan's  Magazine '  for  February  1900  a 
writer  under  the  initials  A.  G.  comments  on  the  con- 
fused position  of  the  subject  in  the  words  : 

On  algebraic  tokens  weird, 

On  decimals  I  daily  pore  ; 
By  these  my  mind  is  nowise  cleared  ; 

They  leave  me  where  I  was  before. 
By  decimals  correctly  done 

Can  Speculation  e'er  be  taught 
To  learn  if  time  begins  at  one 

Or  naught ? 

The  discussions  of  to-day  in  the  Battle  of  the 
Centuries  have  the  same  raison  d'etre  as  those  which 
must  have  been  rife  more  than  a  thousand  years  ago  in 
the  battle  between  the  ordinal  and  cardinal  enumera- 
tion of  the  years  of  what  was  then  the  newly  invented 
era.  But  the  present  position  has  been  further  com- 
plicated by  what  I  trust  I  have  clearly  shown  to  have 
been  a  mistaken  numbering  of  the  B.C.  years. 

But  for  that  mistake  the  Florentine  enumeration, 
after  it  had  displaced  the  Pisan,  must  have  continued 
to  be  treated  as  cardinal,  and  astronomers  would  have 
had  no  reason  for  inventing  a  special  system  for  their 
own  use,  as  their  system  is  in  fact  an  independent 
re-invention  of  the  original  Florentine  system. 

If  1  B.C.  is  to  be  allowed  to  continue  to  immediately 
precede  1  a.d.,  as  it  does  in  our  existing  vulgar  system, 
the  twentieth  century  cannot  commence  until  1900  a.d. 
has  ended;  and  the  German  Emperor's  celebration  of 
the  commencement  of  the  twentieth  century  on  January 
1  of  this  year  (1900)  therefore  virtually  constitutes  a 


HISTORICAL  CHRONOLOGY  67 

step  toward  bringing  vulgar  reckoning  into  accord- 
ance with  that  of  astronomers.  That  celebration  also 
accords  with  the  words  of  the  English  Prayer  Book 
which  declare  the  nineteenth  century  to  be  '  from  the 
year  1800  till  the  year  1899  inclusive.' 

The  Prayer  Book  and  the  German  Emperor  are, 
however,  virtually  in  accordance  with  the  astronomical 
system,  and  their  position  in  the  question  cannot 
logically  be  maintained  without  a  reformation  as 
regards  the  vulgar  numbering  of  the  B.C.  years. 

What  is  wanted  now  to  give  practical  effect  to  the 
reform  which  has  been  virtually  decreed  by  the  German 
Emperor  is  that  some  leading  historical  society  should 
compile  and  publish  a  Chronological  Table  conforming 
with  the  astronomical  method  of  numbering  the  years 
in  both  directions  from  the  present  zero  year  of 
astronomers ;  and  that  the  above  statement  promulgated 
when  the  English  Prayer  Book  was  first  published  should 
be  officially  re-affirmed ;  for  the  position,  according  to 
the  foregoing  argument,  is  such  as  to  make  it  as 
imperative  on  all  nations  who  use  the  era  to  clear  away 
the  error  which  has  crept  into  it,  as  it  was  for  all  who 
aspire  to  the  front  rank  in  civilisation  to  adopt  the 
Gregorian  Keformation. 


68 


ASTEONOMICAL  AxND 


t-  r— 5  --;  L-N.    ;-. 

^    §    S  <M  ^. 

d  it  is  no 
I  have  q 
Astrono 
D.,  being 
ince  the 

Ages,  an 
it,  which 

437  B.C. 
6,  1900  A 
alendar  s 

►^ 

<a 

-o 

a^  >.£:S 

.e 

•^ 

n  lost  in 
Playfair' 
curred  on 
ew  Moon 
d  10  day 

5^ 

'A 

o 

0  have  bee 
pendent  on 
which  oc 
with  the  N 
ng  advance 

O 

M 

■*^  ©  S  Ti  -r: 

C 

S'^  §§  ^ 

■^ 

r. 

i-^sg-^ 

% 

i5 

r. 

r  app 
tness 
New 
omm 
Moon 

a^ 

^ 

in 

.=5 

-S  S  2  "  > 

~i 

;r;  jH^  ja  ^ 

<5j 

,   • 

^§:oi^ 

-^ 

1— 1 

,_ 

^ 

^ 

S5 

identity  of  th 
low,  printed, 
the  Calendar 
Cycle  ended  a 
Bpoch,  the  dat 

H 

dge  of  the 
far  as  I  ki 

epoch  of 
its  123rd 

from  its 

(DO)       -   «• 

•3s>::s 


Qh^ 


1   "=ss^sss2^^:2'*§5s^s"=°E5S 

*         C~CO»OTt<fiO(Nc0005QOfO«5-^CCtHOOiQO 
^                   (MiH          (MrH|<N          (MrH          (MtH          <MtH(MtH 

t>CO»OU5COiN(MOOSOOI>CDiO'*Tt<rHOa5CO 
"MrH          (Mi-i          <M          (M.-I          (MtH          C^rHC<JfH 

O       '                                                                                                                                               1— 1 

i     'p     jOiCOt>COU5^f(5C^l'-lOOiQOI>>«DlOCO(NeOO 

\    f>    i    t>  CO  »o  -*  rc  (M  'M  o  c;  xi  L-  -w  o  '^  CC  iH  o    1  cc 

S     1    OS  00  t- CD  »o -^  cc  <M  tH  O  OS  00  t- CO  «  eo  (N  CO  O 
Hi                 <NrH          (MrH          <MiH0Oi-l          (NnH          (Ni-I|(M 

^           OCS00t>C0l0-*CC<MC0O05X>L--O'>*iCCC<lr-l 
PliH(NiH          (Mi-H          (MrHICQ           (Mi-H          CSJrH           <M 

1 

O           rHOOSOOC^COUtrf«<MrHOClXt~»OTtl?C'M 
J^ii-tSOtH           (MrH           C^r-i           (MrHfMrH           <Ml-H           <M 

1 

5  :  s^g=^S^^^;^^S;^2S=^^s^?5 

1    2^SSS2^g:5^§5S^§^^S'^^ 

S      ,     '^  CO  (M  rH  CO  OS  00  t-  CD  lO  ^  00  IM  rH  O  00  l>  CO  »0 

i               1 

>.    1                                                                                  o 
!     S     1    CD  U5  rP  CO  (M  r-l  O  OS  00  t><0  lO  ^  CO  (M  CO  OS  QO  tr 
h;|,_(          Olrt          (MrH(Mi-l          (Mi-H           (MiHIrH          (N 

1 

HISTOEICAL  CHEONOLOGY 


w 


^      '^  -J  *3 

*=  o  •-  2  2 

-W3  ^  ^  a>  '^ 

id,  w  .«  S  J; 

e3   O   CJ  -^ 

S-^       ..       i^^!       «= 

o  S ,—  o  « 

§^  s^  g 

O  f-1  c3  0)  ts 
^  'o  Is  a>  "^ 
es  aj   g  -  S 

B     -^^  oj 

^    O-    C8    § 

0  .b:      fl  s 

-»^  ^  CO  ^  "^3 
■^  "2  ^  "eS   aJ 

1  ^'^^^ 

^    CI    S 

S§5« 


H     5 


Is 
C3 


o  g-'-'-O  o^ 

QJ    gn    O    c3    g 

1^^  S  =^  2  °^ 
«:3ja  c  =  « 

"iiiif 


!  -1 

1 

Feb.       March      April        May 

^§5S3g^§§^^S3^ssss^§:2 

to  00  (M  <N  O  05  00  C- O  »0  Tfi  T^  rH  O  Oi  00  t- CO  »0     1 

rH 
'^t*  to  (M  Ol  O  Ci  00  C-  O  »C  '^  00  tH  O     1    X  t-  CD  WS 

1 

1     1 

:OCO'*COiMrHOCr5QOC^criOOOiM00005'Xt- 
(MrH          c<irHrOt-l           CTrH           C^rHIOq           (7^1-1 

1 

rH 
l>?D»O'*00<MC0OC:iQ0I>«O-^003<lrHO0i00 
(MtH          (MrH|(M          (MrH          C<lrH          (MrH(Mi-l 

o 

00  t- :£>  »0  tH  CO  (M  1-H  O  OS  00  t>  »0 -^  lO  <M  i-H  O  OS      ! 
C^lrH           (MrH          (N.-I(M.-H          CQrH          OqrHCOrH       | 

i 

Sept.        Oct. 

i 

05  00  t- CO  »o  ■*  CO  <M  ^  CO  05  00  CD  W5  -^  OO  (M  eo  o     1 

(MrH           (MrH           C<lrH|iH          (Mi— 1           C<lrHI<Ml 

th                                    (m          ! 

i 

OOiOOt-COlC^OOCqrHOOSt-COU^rPCCiMrH       ■ 
rHOdrH          (MtH          OJrH           (M           (MrH           (MrH          (N| 

< 

rHO(5(atOOt-COlO"*00(MrHOXt-COIO-*CO(M 
THirH          (MrH           (MrH          (MrHOflrH          (MrH          (M 

July 

rH 

i 

1 

1 

Meton'.s 
Numbers  at 
the  beginning 
of  each  year 

i 

1 

»0  CO  t>  00  <2i  rH  (M  eO  •^  M5  CO  «>  QD  O  O  rH  (M  CO  Tjl      | 
rHrHrHrHrH                                                                      rHrHrHi— li-H 

70 


c3    CI    5- 


Cr:^^  c 

ill  I 

o  a>  o  ^ 

g    c3    O    S 

o   _,  so  o 
«  ^    -  o 

-S  «,<^'  ^ 

g  «=  S  fl 

^     qT    §     eg 
13    P    QJ    g 

-5  °  *^  o 
H  S  o  c 

-2  2'^  I 

So* 

•S      *"  fl 

^  ..fl  ^  rrt 

cS    <^    "^    03 

ns  ^  JJ     • 

C     "^^^ 

^  2"  o 

.2^  s?. 


o   3  S 

a6£ 


Nov. 

OOSOOt*OU5-<<«eO<MfHOOiOC)t-iOrJ<COe<»iH      1 
CO  iH          (N  1-1          (N  tH          (N  rH  0»  tH          W  .-H          «  r-t      1 

Oct. 

cooo500t>«owsTj<eocqrHcocioo:r>tOT*iicc<i 

l<M          (NrH          (MrH          C<l»-ll.-l          C<».-l          (NrH 

Cdi-lOOSQOt-OiO'^COiMi-iOC-.  t-OU5T}tcO 
(M  1-t  <N  iH          (MrH          (N  tH          <N          C<1  iH          (N  iH 

< 

\ 

CO  (M  i-l  CO  05  CD  t*  O  lO -*  CO  Ol  i-l  O  00  t>  O  »0  ■>!*< 
(MrHlr-t          'M.-l          (Mt-1          (NrH(MiH           C^ItH 

1 

1^ 

W5'*co<Ni-ioCiXt:^c:»-'^T*<cciMccc:xc^:c 

(MlH           (Ml-HOli-H           -^^rH           (Mi-llr-l           (Mi-i 

1-5 

iO'*coco<-iooiQor>o»0"*c<:)(N(NC5aot-co 

(MiH          (MiHCMiH          (MrH          (MrH          tH          CQrH 

>> 

1        ^ 

t~COU3T}<CC<MCOOCiQCt>iDO-rt<COrHOCiX 
'MrH           iM^;|(M           IM.H           -MrH           (MrHlMtH 
r-l 

April 

l:-Oi-OlOeO(M(MO(35QOt>OW:'*-*rH03^00 
(MrH          (MrH          <M          (MrH          (MrH           <M  rH   (M  rH 

1 

OS 

o»cx)t*ou:>'<*co(MrHOOioot>o»i:>co(Mcoo 

(MiH          (MrH          (NrHCOrH          (MiH          (MtHICQ 

f 

C-0  0'*CO<M(MOCi(X)t>'^i(5-<#«rHO     1    X 
(MrH          (MrH          (M           IM  rH           (MrH           J<l  rH      IrH 

1     i 
1     *^ 

05a>C-;OiO'<:t»CO(MrHOC5QOt-OXOeO(MCOO 
(MrH          (MrH           (MrHCOrH           (MrH          lMrH|(M 

rH 

oosaot»«ou5'<#cc(McoO(r;(Xit~:0'^co<MrH 

rHCNrH          r:^  ,-^          S<lrHl(M          (MrH          (MrH          (M 

'  1 

1 

;    1 

Meton's 
Numbers  at 
the  beginning 

1 

t-QOosrHS<icO'TiiiocDt>GO(3»OrHe<ieoT}<io(:o 

A/i-J? 


\. 


BY   THE    SAME   AUTHOR. 


ESSAYS    IN    ILLUSTRATION    OF    THE     ACTION    OF 

ASTRAL    GRAVITATION    IN    NATURAL    PHENOMENA.     190U. 
Price  9s, 

THE   STANDARD  OF  VALUE.     Seventh  Edition,  1896. 

Price  5s. 

Preparing. 
FURTHER     ESSAYS     IN     ILLUSTRATION     OF    THE 

ACTION  OF  ASTRAL  GRAVITATION. 

I.     IN  THE  STELLAR  SYSTEM. 

II.    IN  THE  SOLAR  SYSTEM. 

III.  IN  STEEL  RAILS,  This  contains  a  new  explanation  of  the 
mechanical  action  by  which  rails  have  sometimes  been 
broken,  causing  accidents  to  fast  trains  ;  and  also  the  ex- 
position of  an  error  in  the  principles  by  which  Naval 
Constructors  have  been  guided  in  designing  many  of  the 
fast  ships  now  afloat,  and  by  which  they  profess  still  to  be 
guided. 

IV.     ON  THE  PENDULUM. 


r.ONGMANS,  GREEN,  &  CO.,  39  Paternoster  Row,  London, 
New  York  and  Bombay. 


UNIVERSITY  OF  CALIFORNIA  LIBRARY 
This  book  is  DUE  on  the  last  date  stamped  below. 

Fine  schedule:  25  cents  on  first  day  overdue 

f^r^?'^'"^'"^''^0'cen^  on  fbuiift?^dvefdue  "^^ 
One  dollar  on  j^^th  day  overdue. 


OCT   14  1947 


6Jan'53LW 
lJun'54BMt 


17May64Sp 


CAY  1 3 '64 -U  AM 


m 


LD  21-100m-12,'46(A2012sl6)4120 


iJO£ 

r 


U.C.BERKELEY  LIBRARIES 


i 


CD^t,DSD^l7 


